@string{JASA = "Journal of the Acoustical Society of America"}
@string{JFI = "Journal of the Franklin Institute"}
@string{PHYREV = "Physical Review"}
@string{PNAS = "Proceedings National Academy Science"}
@string{BLR = "Bell Laboratories Record"}
@string{BSTJ = "Bell System Technical Journal"}
@string{PIRE = "Proceedings of the I.R.E."}

@article{Fletcher11a,
author={Millikan, R.A. and Fletcher, H.},
title={A contribution to the theory of {B}rownian movements, with
experimental applications},
journal=PHYREV,
year={1911},
month=feb,
volume={32},
pages={251},
note_={Also in {\em Physikalische Zeitschrif}, Jan 12, 1911, pp. 202-208.}}

@article{Fletcher11b,
author={ Millikan, R.A.  and Fletcher, Harvey },
title={On the question of valency in gaseous ionization},
year={1911},
journal=PHYREV,
month=feb,
volume={32},
pages={239},
note_={Also in Phil. Mag. 21:753--70, June 1911.} }

@article{Fletcher11c,
author={Fletcher, Harvey},
title={A verification of the theory of {B}rownian movements and a
direct determination of the value for {N}e for gaseous ionization},
journal=PHYREV,
year={1911},
month=aug,
number={2},
volume={33},
pages={81--110},
note_={Also in {\em Physikalische Zeitschrif} XII (1911) pp. 202--208.
According to
Millikan, Fletcher published similar work in {\em Le Radium} (July), VIII
(1911), p. 279.  See also Science 32, 436--8; {\em Physikalische Zeitschrif},
11, 1097--1109; Le Radium, 7, 341--61} }

@article{Fletcher11d,
author={Millikan, R.A. and Fletcher, Harvey},
title={Causes of apparent discrepancies in recent work on the
determination of the elementary electrical charge},
journal={Physikalische Zeitschrift},
year={1911},
month=jan,
volume={},
number={},
pages={161--163},
note_={ } }

@article{Fletcher14,
author={Fletcher, Harvey},
title={Determination of {A}vogadro's constants {N} from
measurements of the {B}rownian movements of small oil drops in air},
journal=PHYREV,
year={1914},
month=nov,
volume={4},
number={5},
pages={440--453},
note_={} }

@article{Fletcher15,
author={Fletcher, Harvey},
title={Upon the question of electric charges which are smaller than the
electron },
journal={Physikalische Zeitschrif},
year={1915},
month=jan,
volume={16},
pages={316--318},
note_={In german only ``Uber die frage der elektrizitatsladungen,
welche die der elektronen unterschreiten.''} }

@article{Fletcher20,
author={Fletcher, Harvey},
title={The relative difficulty of interpreting the spoken sounds of {E}nglish},
journal=PHYREV,
year={1920},
month=jun,
volume={15},
pages={513--516},
note_={Also published in {\em Physikalische Zeitschrif} (August?)} }

@article{TM21-101-6,
author={Fletcher, Harvey},
title={An empirical theory of telephone quality},
journal={AT\&T Internal Memorandum},
year={1921},
month=oct,
volume={101},
number={6},
note_={First document about the Articulation Index. Case 211031, report 21839.
The only know copy is in Fletcher's archives, Brigham Young University,
Provo UT. (UA029, Box 19 \#2, MSS1233)} }

@article{Fletcher22
,author={Fletcher, Harvey}
,title={Unknown}
,journal=PHYREV
,year=1922
,month=may
,volume={19}
,number={}
,pages={492}
,note={Ref. 9 in Fletcher's 1930 JASA paper .} }

@article{Fletcher22a,
author={Fletcher, Harvey},
title={The nature of speech and its interpretation},
journal=JFI,
year={1922},
month=jun,
volume={193},
number={6},
pages={729--747},
note={Also in the BSTJ, 1922, July, Vol. i, pp 129-144.},
note_={Plots of articulation as a function of level, and as a
function of high-pass and low-pass cutoff frequency. Articulation
for different speech sounds, for both level and cutoff frequency.
Classifies speech sounds into three categories, based on
articulation as a function of filter cutoff frequency.
Shows that articulation is not additive, as assumed by
Crandall in 1917. First paper to use filtering to modify
articulation.  This paper was awarded the Louis Edward
Levy gold medal (See Journal of the Franklin Institute,
197 p.~708, 1924). See also ``History of Harvey Fletcher''
\cite[p.~50]{Fletcher67}.
}}

@article{Fletcher22a_,
author={Fletcher, Harvey},
title={The nature of speech and its interpretation},
journal=BSTJ,
year={1922},
month=jul,
volume={i},
pages={129--144},
note_={Same as \cite{Fletcher22a}.} }

@article{Fletcher22b,
author={Fletcher, Harvey and Wegel, R.L.},
title={The Frequency-Sensitivity of Normal Ears},
journal=PHYREV,
month=jun,
year={1922},
volume={19},
pages={553--565},
note={also in PNAS 1922, Jan., Vol. 8, No. 1, pp 5-6.},
note_={ Work started in 1920 to determine the absolute sensitivity
of the Ear. They used the thermophone formula. See \cite{Fletcher29a}
p.~134. AT\&T monograph B--8--1} }

@article{Fletcher22c,
author={Fletcher, Harvey and Wegel, R.L.},
title={The frequency-sensitivity of normal ears},
journal=PNAS,
month=jan,
year={1922},
volume={8},
number={1},
pages={5--6},
note={also in PHYREV 1922, June Vol. 19, pp 553-565.},
note_={ Talk with two figures. See \cite{Fletcher22b}.}	}

@article{TM22-198-6,
author={Fletcher, Harvey},
title={Fundamental studies in the transmission of speech},
journal={AT\&T Internal Memorandum},
year={1922},
month=feb,
volume={198},
number={6},
pages={},
note_={cases: 320311,30945,320254} }

@article{TM22-249-5,
author={Fletcher, Harvey},
title={The study of telephone quality outlines case 32--311},
journal={AT\&T Internal Memorandum},
year={1922},
month=may,
volume={249},
number={5},
pages={},
note_={Re-groups all cases into single new case 320311.} }

@article{TM22-338-5,
author={Fletcher, Harvey},
title={Discussion of the proposed transmission efficiency units},
journal={AT\&T Internal Memorandum},
year={1922},
month=aug,
volume={338},
number={5},
pages={},
note_={Case number unknown} }

@article{TM23-780-6,
author={Fletcher, Harvey},
title={Noise measurements on subway trains},
journal={AT\&T Internal Memorandum},
year={1923},
month=sep,
volume={780},
number={6},
pages={},
note_={case 32182}
	}

@article{Fletcher23a,
author={Fletcher, Harvey},
title={Physical Measurements of Audition and their Bearing on the
Theory of Hearing},
journal=JFI,
year={1923},
month=sep,
volume={196},
number={3},
pages={289--326},
note_={Physical measurements of audition, with complete and partially
annotated bibliography of the subject. Loudness measurements are described.
It seems that this is where he first found that loudness grows as $p^{2/3}$.
He gives a formula for the number of JNDs, and presents Wegel and Lane's
masking data, before Wegel and Lane, and refers to the not yet published
Wegel and Lane paper.}
	}

@article{Fletcher23a_,
author={Fletcher, Harvey},
title={Physical Measurements of Audition and their Bearing on the
Theory of Hearing},
journal=BSTJ,
year={1923},
month=oct,
volume={ii},
number={4},
pages={145--180},
note_={Same as \cite{Fletcher23a}, with full bibliography.} }

@article{Fletcher23c,
author={Fletcher, Harvey},
title={The use of the audiometer in prescribing aids to hearing},
journal={Trans. Coll. of Physicians of Phila.},
year={1923},
month=apr,
volume={45},
number={3},
pages={489},
note_={First paper describing the Audiometer. Copy in BYU archive.} }

@article{Fletcher24a,
author={Fletcher, Harvey and Steinberg, J.C.},
title={The dependence of the loudness of a complex sound upon the
energy in the various frequency regions of the sound},
journal=PHYREV,
year={1924},
month=sep,
volume={24},
number={3},
pages={306--317},
note_={ 
This paper deals with the loudness of filter speech and of
complex tones consisting of line spectra.
The signal was first low- and high-pass filtered, and compared
to the original unfiltered signal, which had been attenuated
to match the filtered signal in loudness.
They found that the loudness sums intensity
for levels below 30 dB SL. Above 30 dB, the loudness sums
as $I^{1/3}$.
They wrote about loudness in terms of ``nerve terminals.''
This showed that they were thinking in terms of physiological
systems in 1924.}
	}
 note_={
For example, if $s$ is the speech,
$G$ is some gain parameter modifying the speech, giving $G*s$,
$LP(s)$ and $HP(s)$ are the filtered speech,
and $L(G*s)$ is the loudness of the attenuated speech, then 
they found $G$ such that $L(G*s) = L(LP(s))$ .
Similarly for the high-pass filtering. This was a loudness
summation experiment.
This was done by finding the power law that made the low-pass
part and the high-pass part sum to 1 at the crossover frequency.
Namely if the HP and LP are set to the frequency where
$L(LP(s)) = L(HP(s))$ then power $b$ was found such that
$L(LP(s))^b + L(HP(s))^b =L(s)$.
At levels below 30 dB SPL $b$ was 1.
At levels above 30 dB, $b=1/3$.
Note the similarity between this formula and the summation rules
described by Lutfi and Humes.

When distortion (i.e. harmonic distortion) was present (as in the case
of a distorting (nonlinear) filter), it would contribute to the loudness.
In this case the distortion must be accounted for in the theory.

These experiments were obviously related to the problem of
studying the loudness of speech in the telephone network.

They concluded: ``it became apparent that the non-linear character
of the ear transmitting mechanism was playing
an important part in determining the loudness of complex tones.''
The ``ear transmitting mechanism'' is a reference to the middle ear.
And: ``There is a great deal of evidence that the elastic members
taking part in the transmission of sound to the inner ear fail to
obey Hooks's law when the intensity of the sound becomes
sufficiently great (Wegel and Lane, Phys. Rev. v. 23, p.\ 266 1924).
The levels of this nonlinearity were given to be between 20--40
sensation units above threshold.
And ``For very low frequencies, the non-linearity begins even at
the lower levels.''
They described how the ``ear transmitting mechanism'' acts as a
filter. By this they are referring to the middle ear transmission.
This point seems to have been first made by Wegel and Lane (1924).

Regarding the $b=1/3$ region, they say ``The net result of the
distortion is to bring into greater prominence the lower
frequency regions of the sound.''

Finally, they explained that speech and complex tones have different
loudness patterns. At this point they stated that they had not related
the two cases, due to a lack of data. However, the new data had
been obtained, and would be presented in a future paper.

This paper was submitted to JASA four months after the creation
of {\em The Bell Telephone Laboratories}.  }	

@article{Fletcher24b,
author={Fletcher, Harvey},
title={Audiometric measurements and their uses},
journal={Volta Review},
year={1924},
month=jan,
volume={26},
pages={10--14},
note_={See also \cite{Fletcher23c}.
The paper is about the Western Electric audiometers.} }

@article{Fletcher24d,
author={Fletcher, Harvey},
title={Some further experiments of the pitch of musical tones},
journal=PHYREV,
year={1924},
month=jan,
volume={23},
pages={117--118},
note_={} }

@article{Fletcher24c,
author={Fletcher, Harvey},
title={The physical criterion for determining the pitch of a musical tone},
journal=PHYREV,
year={1924},
month=mar,
volume={23},
number={3},
pages={427--437},
note_={} }

@article{Fletcher24e,
author={Fletcher, Harvey},
title={Sound magnification and its application to the requirements
of the deafened},
journal={Volta Review},
year={1924},
month=sep,
volume={24},
pages={441--449},
note_={} }

@techreport{Fletcher24f,
author={Fletcher, Harvey},
title={The physical properties of Speech, music and noise and
their relation to transmission problems},
institution={American Telephone and Telegraph},
year={1924},
type={Monograph},
number={B--94--1},
month=feb,
address={AT\&T Archives, 91 Rieman Rd, Warren NJ},
note_={Unpublished address delivered before a joint meeting of the NY
Electrical Soc.\ and the NY Telephone Soc.\ NY, NY, Feb.\ 1924.  } }

@article{Martin24,
author={Martin, W.H. and Fletcher, Harvey},
title={High quality transmission and reproduction of speech and
music},
journal={Trans. Amer. Inst. Elec. Eng.},
year={1924},
month=mar,
volume={43},
pages={384--392},
note_={monograph B--82--1; See also {\em Elect. Com.} in April.} }

@article{Fletcher25a,
author={Fletcher, Harvey and Lane, C.E.},
title={Development of the Artificial Larynx},
journal={Western Electric News},
month=jan,
year={1925},
volume={},
pages={},
note_={ See Crandall's book p.\ 253 for more on this, about the
Artificial Larynx. See also the Philadelphia Record of Jan. 18,
1925. See TM24--1019--6} }

@article{Fletcher25b,
author={Fletcher, Harvey},
title={Useful Numerical Constants of Speech and Hearing},
journal=BSTJ,
year={1925},
month=jul,
volume={iv},
number={3},
pages={375--386},
note_={Very useful reference.} }

@article{Fletcher25c,
author={Fletcher, Harvey},
title={How an electrical hearing aid works},
journal={Volta Review},
year={1925},
month=nov,
volume={27},
pages={607--609},
note_={} }

@article{Fletcher25d,
author={Fletcher, Harvey},
title={Man-made ears for the deaf: why many deaf people hear
normally in noisy places and over the telephone. {N}ew advances in
sound amplifiers.},
journal={Scientific American},
year={1925},
month=nov,
volume={133},
pages={320--321},
note_={Defined \% of Hearing Loss. Used Speech \% correct versus
level. Points importance of covering the mouth-piece to improve
telephone communications when using the telephone in high-noise
environments.} }

@article{Fletcher25e,
author={Fletcher, Harvey},
title={New methods and apparatus for testing hearing},
journal={Annals of Otology, Rhinology and Laryngoscope},
year={1926},
month=mar,
volume={},
pages={},
note_={monograph B--152--1} }

@article{Fletcher25f,
author={Fletcher, Harvey},
title={Audiometric measurements and their uses},
journal={Trans. Coll. of Physicians of Phila.},
year={1923},
volume={},
number={},
pages={},
note_={Copy in BYU UA-029, Box 7} }

@article{Fletcher25g,
author={Fletcher, Harvey},
title={Some new methods and apparatus for testing the acuity of
hearing and their relation to the speech and tuning fork methods},
journal={The Laryngoscope},
year={1925},
month=jul,
volume={35},
number={7},
pages={1--24},
note_={} }

@article{Fletcher26a,
author={Fletcher, Harvey},
title={Measuring children's hearing},
journal=BLR,
year={1926},
month=jun,
volume={2},
number={4},
pages={154--157},
note_={Discusses the 4A audiometer, Phonograph audiometer, and
{\em The League for the Hard of Hearing}, NYC} }

@article{Fletcher26b,
author={Fletcher, Harvey},
title={The theory of the operation of the howling telephone with
experimental confirmation},
journal=BSTJ,
year={1926},
volume={v},
month=jan,
pages={27--49},
note_={This may be the first mathematical analysis of feedback. One year
later, Black invented negative feedback, which ranked with the
invention of the audion.  In 1932, Nyquist published
his famous test of stability. Monograph B--185} }

@article{Fletcher26c,
author={ Fowler, E.P.  and Fletcher, Harvey },
title={Three million deafened school children},
journal={Jol. Amer. Med. Assoc.},
year={1926},
month=dec,
volume={87},
number={},
pages={1877--82},
note_={ }}

@article{Fletcher26d,
author={Fletcher, Harvey },
title={Comparison of the results made with two types of audiometers},
journal={Archives of Otolaryngology},
year={1926},
month=jul,
volume={4},
number={},
pages={51--57},
note_={ }}

@article{Fletcher27,
author={Fletcher, Harvey},
title={Hearing aids and deafness},
journal=BLR,
year={1927},
month=oct,
volume={5},
number={2},
pages={33--38},
note_={6034A audiophone, loudness, and sensation units} }

@article{Fletcher27b,
author={Fletcher, Harvey},
title={Demonstration of principles of talking and hearing with
application to radio},
journal={Ann. Othl. Rhinol. Laryngol.},
year={1927},
month=mar,
volume={},
pages={},
note_={} }

@article{Fletcher27c,
author={Fletcher, Harvey},
title={The hard-of-hearing child},
journal={US School Health Studies},
year={1927},
volume={13},
month=jul,
pages={},
note_={} }

@article{Fletcher28,
author={Fletcher, Harvey},
title={Book review {{\em {T}he {T}heory of {S}ound}} by {L}ord {R}ayleigh},
journal={Proceedings of the Inst. of Radio Engineers},
year={1928},
month=may,
volume={16},
pages={681--691},
note_={} }

@book{Fletcher29a,
author={Fletcher, Harvey},
title={Speech and Hearing},
year={1929},
publisher={D. Van Nostrand Company, Inc., New York},
note_={According to the preface of the 1953 edition (i.e., this book),
this material was published after 15 years of work, which would mean that
the effort began in 1914 with Crandall.} }

@article{Fletcher29b,
author={Fletcher, Harvey and Steinberg, J.C.},
title={Articulation Testing Methods},
journal=BSTJ,
year={1929},
month=oct,
volume={8},
pages={806--854},
note_={Also in Jol. Acoust. Soc. Am.(1930), Vol 1, No. 2: 1--113 (Special edition)
Discussion of history of articulation measures.
Plots of word articulation vs. syllable articulation, with
theoretical curves superimposed. B--436}	}

@article{Fletcher29c,
author={Fletcher, Harvey},
title={Physical Aspects of Audition},
journal={International Critical Tables},
year={1929},
volume={6},
pages={450--453},
note__={530.08 N27} }

@article{Fletcher29d,
author={Fletcher, Harvey},
title={What can {I} do},
journal={Volta Review},
year={1929},
month=oct,
volume={31},
pages={637--642},
note_={Religious style talk about hearing impairment.} }

@article{Fletcher30a,
author={Fletcher, Harvey},
title={A space-time pattern theory of hearing},
journal=JASA,
year={1930},
month=apr,
volume=1,
number=1,
pages={311--343},
note_={
This theory of the cochlea predates Ranke, but not Wegel and Lane (1924).
The paper was written after \cite{Fletcher29a} and clearly
shows the progression of Fletcher's thinking in 1930.
He concludes the ear drum impedance must
be stiffness dominated at lower frequencies ($<$1000 Hz) (p. 314).
He then estimates the variation of cochlear map
from physical properties, such as the width of the BM.
He rejects the von B\'ek\'esy eddy theory.
Using the cochlear map and pure tone masking
data, he plots excitation ``space'' patterns as a function of level.
Discusses a ``spread of excitation'' model of loudness.  }}
note_={ Points out that Wegel and Lane data are on Fletcher's left
ear (Page 325).

The non-linear character of the middle ear with subjective
harmonics is discussed.  ``These space patterns for the entire length
of the membrane, however, can be obtained form the masking data.''
Did he clearly have the concept of the critical band in mind in 1930?
Read this paper to find out.

"There is no doubt that loudness is closely associated with the
total discharges reaching the brain." Page 336
Page 339 determines the level a 1kHz tone so that its loudness equals
that of 6 tones of equal SPL (-20 dB re ?).

Several minor errors: he confuses the fundamental and the
first harmonic (page 315), after carefully defining it (page 313).
Is the word ``phrases'' a typo, that should have been ``phases''
on p.\ 311, item (4) of second set of items? B--499
	}

@article{Fletcher30b,
author={Fletcher, Harvey},
title={Acoustic engineers credit recent marked progress to
electronic tools},
journal={Electronics},
year={1930},
month=may,
volume={1},
pages={61},
note_={} }

@article{Fletcher30c,
author={Fletcher, Harvey},
title={Physical factors affecting the perception of sound},
journal={Auditory Outlook},
year={1930},
month=oct,
volume={1},
pages={357--364},
note_={} }

@article{Fletcher30d,
author={Fletcher, Harvey},
title={The progress of hearing tests in the public schools of the
{U}nited {S}tates},
journal={Volta Review},
year={1930},
month=jan,
volume={32},
pages={1--4},
note_={} }

@article{Fletcher30e
,author={Fletcher, H. and Steinberg, J.C.}
,title={Articulation testing methods}
,journal=JASA
,year=1930
,month=jan
,volume=1
,number=2
,pages={17-113}
,note={Intelligibility Lists pages 65-113} }

@article{Fletcher31,
author={Fletcher, Harvey},
title={Some Physical characteristics of speech and music},
journal=BSTJ,
year={1931},
month=jul,
volume={10},
pages={349--373},
note_={Also in Rev.\ Mod.\ Phys., 10:349--73, April, 1931.
A discussion of some of the physical
characteristics of unreflected speech and musical sounds. B--568} }

@article{Fletcher31a
,author={Fletcher, Harvey}
,title={Some Physical characteristics of speech and music}
,journal=JASA
,year=1931
,month=oct
,volume={3}
,number={2.2}
,pages={1-25}
,note={} }

@article{Fletcher31b,
author={Fletcher, Harvey},
title={Our outlook},
journal={Auditory Outlook},
year={1931},
month=apr,
volume={2},
pages={149--151, 199--200},
note_={This is the journal of the Amer. Federation of Orgs.  for the
Hard of Hearing. In Jan. of 1934 it was merged with Volta Review,
which was Bell's Journal for deaf research.} }

@article{Fletcher32a,
author={Fletcher, Harvey},
title={The loudness of sound. {T}he sensitivity limits of the human ear},
journal={Wireless World},
year={1932},
month=jul,
volume={31},
pages={78--80},
note_={} }

@inproceedings{Fletcher32b,
author={Fletcher, Harvey},
editor={
Page, Arthur W. and
Arnold, H.D. and
Fletcher, Harvey and
Brown, Ralph and
Otterson, John, E. and
Jewett, Frank B. and
Ives, Herbert E.
	},
title={Researches in Speech and Hearing},
booktitle={Modern Communication},
volume={},
year={1932},
pages={49--76},
publisher={Houghton},
address={},
note_={Seven papers constituting this book were delivered in the
form of lectures for a Lowell Institute course in Boston, MA in
January, 1932.} }

@article{Fletcher32c,
author={Fletcher, Harvey},
title={Can we scientifically advise patients as to the
effectiveness of hearing aids?},
journal={Ann. Otol. Rhinol. Laryngol.},
year={1932},
month=sep,
volume={41},
pages={727--739},
note_={} }

@article{Fletcher33a,
author={Fletcher, Harvey and Munson, W.A.},
title={Loudness, Its Definition, Measurement, and Calculation},
journal=JASA,
year={1933},
volume={5},
pages={82--108},
note_={The classic paper on loudness. A must.
The loudness of complex tones having random phases,
with masking effects, is discussed in detail.
Formulae for the effects of masking of one tone by
another are developed based on loudness studies.
In this paper the concept of the critical band is clearly
stated for the first time (p.\ 97--8). The critical band
is necessary when components are too close in frequency.
The masking is treated using factor $b_k$ on the $k^{th}$
loudness component. These factors may be computed from the relations of
the paper (Eq. 21). When the components are all equal in
loudness, Eq. 17 may be used. When no masking occurs, the
factors are unity, and the loudness is shown to add.
The ``direct'' method is compared to the loudness matching results.
The model is extensively compared to real examples. The exact
procedure used to measure the loudness is described in the
appendix A.
Reprint B--756} }

@article{Fletcher33a_,
author={Fletcher, Harvey and Munson, W.A.},
title={Loudness, Its Definition, Measurement, and Calculation},
journal=BSTJ,
year={1933},
month=oct,
volume={xii},
pages={377--430},
note_={Same as \cite{Fletcher33a} publication.} }

@article{Fletcher33b,
author={Fletcher, Harvey},
title={An acoustic illusion telephonically achieved},
journal=BLR,
year={1933},
month=jun,
volume={11},
number={10},
pages={286--289},
note_={Systems of transmission divided into four classes; Oscar,
the tailor dummy, Amer. Academy of Music in Philadelphia,
diotic, binaural, and monaural systems.} }

@article{Fletcher33c,
author={Fletcher, Harvey},
title={Evaluating hearing aids},
journal=BLR,
year={1933},
month=jan,
volume={11},
number={5},
pages={126--133},
note_={The successive sounds of speech vary considerably in
loudness; hearing loss that exceeds limitations; pitch.} }

@article{Fletcher33d,
author={Fletcher, Harvey},
title={The relation of the reference level for loudness and
intensity measurements of sound to the thermal noise level in
electrical and acoustical circuits},
journal=JASA,
year={1933},
month=jul,
volume={5},
pages={65--66},
note_={} }

@article{Fletcher33e,
author={Fletcher, Harvey},
title={Sound measurement},
journal={Elec Eng},
year={1933},
month=mar,
volume={52},
pages={199},
note_={} }

@article{Fletcher34a,
author={Fletcher, Harvey},
title={Symposium on wire transmission of symphonic music and its
reproduction in auditory perspective: Basic requirements},
journal=BSTJ,
year={1934},
month=apr,
volume={xiii},
pages={239--244},
note_={See also Electrical Engineering, Vol 53, p. 9--32,
216--218. Jan., 1934. One of a series of papers on
{\em Auditory Perspective} having several authors (B--784).} }

@article{Fletcher34b,
author={Fletcher, Harvey},
title={Loudness, pitch, and the timbre of musical tones and their
relation to the intensity, the frequency, and the overtone structure},
journal=JASA,
year={1934},
month=oct,
volume={6},
number={2},
pages={59--69},
note_={B--824} }

@article{Fletcher34c,
author={Fletcher, Harvey},
title={Transmission and reproduction of speech and music in
auditory perspective},
journal={Jol. of SMPTE},
year={1934},
month=may,
volume={22},
pages={314--329},
note_={ } }

@article{Fletcher34d,
author={Fletcher, Harvey},
title={Hopeful trends in the testing of hearing and in the
prescribing of hearing aids},
journal={Proc. Amer. Federation of Organizations for the Hard of
Hearing},
year={1934},
month=oct,
volume={},
pages={},
note_={Reprint no. 85} }

@article{Fletcher35a,
author={Fletcher, Harvey},
title={Loudness and Pitch},
journal=BLR,
year={1935},
month=jan,
volume={13},
pages={130--135},
note_={} }

@article{Fletcher35b,
author={Fletcher, Harvey},
title={Newer concepts of the pitch, the loudness,
and timbre of Musical Tones},
journal=JFI,
year={1935},
month=oct,
volume={220},
number={4},
pages={405--429},
note_={References Stevens JASA paper of Jan. 1935. (B--896)} }

@article{Fletcher37a,
author={Fletcher, Harvey and Munson, W.A.},
title={Relation Between Loudness and Masking},
journal=JASA,
year={1937},
volume={9},
pages={1--10},
note_={
First paper to explore the critical band in detail.
This paper was used in Chapter 4 of Stevens and Davis, 1938.
They showed that the cochlear map function and the critical
bandwidths are closely related functions, and argued that they
could be derived from each other (see \cite{Fletcher38a}).
This paper was the first to normalize the cochlea in terms of the
percent of its full length.
Presented at the Acoustical Society meeting, May 1937.  }
	}
note_={
The problem is to relate the loudness of a continuous
spectrum, thermal noise, to the masking pattern $M(x)$, where $x$
is the positional coordinate along the basilar membrane.
The idea is to reduce the complex problem to a simpler one
through the known nonlinear mappings between place and frequency
(the cochlear map) and loudness (the cube root loudness growth law).
They used wide band masking noise having uniform masking across frequency
to simplify the integration over place. For the uniform masking noise
they found a near linear relation between intensity and masked
threshold with 27 dB difference.
They then measured the loudness growth of the uniform masking noise.
Using the known loudness function from 1933, the loudness for the
uniform masking noise is transformed to LU (or Sones, using todays
terminology). This gave the function $F(M)$ which is the
loudness density in terms of masking $M(x)$ along the basilar membrane.
Using this function, one can accurately determine the loudness
from a measured masked threshold. This was then tested using
critical band, medium bandwidth and tone maskers.
The ratio, in dB, between the spectral level and the masked threshold
was called the {\em critical band}. It was found to be a function of
frequency and was first plotted in this paper (Fig 16) 
(see also \cite[Fig. 2]{Fletcher38b} for details on how $\kappa$ was derived).
Using the critical band, the effective level $Z$ of the signal was
derived. This is equivalent to the ``excitation pattern'' of today.
The effective level is given by $Z=B-\beta_0 + \kappa$, where $B$
is the spectral level of the stimulus, $\beta_0$ is the hearing
threshold, and $\kappa$ is the critical bandwidth. They then
determined the relation between $M$ and $Z$ which was almost
unity except below 20 dB and above 60 dB. The high level
departure from unity is most interesting as it seems to be a
change in the critical bandwidth with level. They now had
relations between $F$ and $M$ and between $M$ and $Z$. They could
therefore solve for $F$ as a function of $Z$. They called this
function $Q$. Given $Q$ (Fig. 18) one can find the loudness of a
continuous spectrum from the effective level $Z$, which is easily
calculated from the input signal and the hearing threshold $\beta_0$.
B--1015}

@article{Fletcher37b,
author={Fletcher, Harvey},
title={Anatomy and Physiology. {V}iewpoint of the Physicist},
journal={Laryngoscope},
year={1937},
month=jun,
volume={47},
pages={389--394},
note_={} }

@article{Fletcher38a,
author={Fletcher, Harvey},
title={Loudness, Masking and Their Relation to the Hearing
Process and the Problem of Noise Measurement},
journal=JASA,
year={1938},
month=apr,
volume={9},
pages={275--293},
note_={
This is the first time that the cochlear map is derived from
critical band masking data. It is compared to that derived from
pitch experiments, and found to be similar. Thus a relation
between the frequency JND and masking is demonstrated.
The formula for $\kappa$ the critical bandwidth in dB is
described here in Eq. 15. A plot is given in Fig. 6.
He calculates the signal to noise ratio at the masked threshold and
finds it to be 0.5 dB, except at low levels where it is 3 to 4 dB
(p.\ 284).  The relation between the loudness and the masked threshold
for any sound is described.
These data are refinements on \cite{Fletcher37a}.  B--1067} }

@article{Fletcher38b,
author={Fletcher, Harvey},
title={The mechanism of hearing as revealed through experiments on
the masking effect of thermal noise},
journal=PNAS,
year={1938},
volume={24},
pages={265--274},
note_={First gives raw data (e.g., Fig. 121 of \cite{Fletcher53})
on computing the critical band from wide-band noise masking data.
This paper is referred to in \cite{Fletcher40a}.
} }

@article{Fletcher38c,
author={Fletcher, Harvey},
title={Noise measurements and the International Conference on Acoustics},
journal=BLR,
year={1938},
month=feb,
volume={16},
number={2},
pages={213--216},
note_={New York survey; international standards association;
electrotechnical commission; loudness measurements; an acoustical
conference.} }

@article{Fletcher40a,
author={Fletcher, Harvey},
title={Auditory Patterns},
journal={Reviews of Modern Physics},
year={1940},
month=may,
volume={12},
number=1,
pages={47--65},
note_={This is a review/tutorial article. Fletcher states that the
development of the instrumentation required to study the ear
led to the development of radio and sound pictures.
This paper has been heavily referred to because it describes some
direct critical band measurements.
Many have referenced this paper as the first to introduce the
critical band, which is incorrect.
It has a basic review of the calculation of $C$ and the cochlear map.
Bell Labs monograph B--1205} }

@article{Fletcher40b,
author={Fletcher, Harvey},
title={Stereophonic reproduction from film},
journal=BLR,
year={1940},
month=may,
volume={18},
number={9},
pages={260--265},
note_={Enhancement control unit} }

@article{Fletcher41a,
author={Fletcher, Harvey},
title={Stereophonic sound film system -- General Theory},
journal=JASA,
year={1941},
month=oct,
volume={13},
pages={89--99},
note_={B--1327} }

@article{Fletcher41b,
author={Fletcher, Harvey and Snow, W.B.},
title={Stereophonic sound film system: Theory and performance of
compandor systems},
journal={Int. Projectionist},
year={1941},
month=mar,
volume={16},
pages={27--28},
note_={} }

@article{Fletcher42a,
author={Fletcher, Harvey},
title={Hearing, The determining factor for high-fidelity transmission},
journal={Proceedings of the Inst. of Radio Engineers},
year={1942},
month=jun,
volume={30},
pages={266--277},
note_={B--1351} }

@book{Fletcher44a,
author={Fletcher, Harvey},
title={Scientific progress and civic responsibility},
year={1944},
month=jun,
publisher={Univ.\ of Utah Press},
note_={} }

@article{Fletcher46a,
author={Fletcher, Harvey},
title={Pitch, Loudness and quality of musical tones},
journal={Amer. Jol. Phys.},
year={1946},
month={Jul--Aug},
volume={14},
pages={215--225},
note_={B--1397} }

@article{Fletcher46b,
author={Fletcher, Harvey},
title={The atomic bomb},
journal={The Improvement Era},
year={1946},
month=mar,
volume={},
pages={},
note_={} }

@article{Fletcher47a,
author={Fletcher, Harvey},
title={An institute of musical science--A suggestion},
journal=JASA,
year={1947},
month=jul,
volume={19},
pages={527--531},
note_={} }

@article{Fletcher47b,
author={Fletcher, Harvey},
title={Modern version of the old theory of telephone quality},
journal=JASA,
year={1947},
month=jan,
volume={19},
number={1},
pages={291--292},
note_={Abstract of Internal Memorandum \cite{TM47-110-50}.} }

@article{TM47-110-50,
author={Fletcher, Harvey},
title={A modern version of the old theory of telephone quality},
journal={AT\&T Internal Memorandum},
year={1947},
month=jul,
volume={110},
number={50},
pages={1--124},
note_={Good discussion of history of articulation, with more
complete theory. Extensions of the earlier theory
inspired by Harvard work headed by S.S. Stevens
during the war, using high noise and narrow bandwidth systems.
Finally published as \cite{Fletcher50a}.
} }

@article{Fletcher47c,
author={Fletcher, Harvey},
title={Science of Hearing},
journal={The Scientists Speak},
year={1947},
volume={},
publisher={Boni and Gaer},
address={New York, NY},
pages={246--249},
note_={Edited by Warren Weaver. Vol. 771, p.\ 129, NYC Public Lib.
index. A series of radio programs given during the intermissions
of NY Philharmonic Symph. broadcasts.} }

@article{Fletcher48a,
author={Fletcher, Harvey},
title={Science of Hearing},
journal={Volta Review},
year={1948},
month=aug,
volume={50},
pages={351--352},
note_={} }

@article{Fletcher48b,
author={Fletcher, Harvey},
title={Perception of speech and its relation to telephony},
journal={Science},
year={1948},
month=dec,
volume={108},
pages={682},
note_={} }

@article{Fletcher50a,
author={Fletcher, Harvey and Galt, R.H.},
title={Perception of speech and its relation to telephony},
journal=JASA,
year={1950},
month=mar,
volume={22},
pages={89--151},
note_={The tome. Same as Chapter 15 of \cite{Fletcher53}. See
Errata: JASA 1950, p.\ 327} }

@article{Fletcher50b,
author={Fletcher, Harvey},
title={A method of Calculating Hearing Loss for Speech from an Audiogram},
journal=JASA,
year={1950},
month=jan,
volume={22},
pages={1--5},
note_={B--1731} }

@article{Fletcher51a,
author={Fletcher, Harvey},
title={On the dynamics of the cochlea},
journal=JASA,
year={1951},
month=nov,
volume={23},
pages={637--645},
note_={Theory of cochlea, including scalae viscosity. Matches von
B\'ek\'esy data.} }

@article{Fletcher51b,
author={Fletcher, Harvey},
title={Acoustics},
journal={Phys Today},
year={1951},
month=dec,
volume={4},
pages={12--18},
note_={Details on the theory of the cochlea, similar to \cite{Fletcher51a}.} }

@article{Fletcher52a,
author={Fletcher, Harvey},
title={Dynamics of the middle ear and its relation to the acuity
of hearing},
journal=JASA,
year={1952},
month=mar,
volume={24},
pages={129--131},
note_={} }

@article{Fletcher52b,
author={Fletcher, Harvey},
title={The perception of speech sounds by deafened persons.},
journal=JASA,
year={1952},
month=sep,
volume={24},
number={5},
pages={490--497},
note_={Evaluation of the Harvard hearing aid report by articulation
index methods.} }

@book{Fletcher53book,
author={Fletcher, Harvey},
title={Speech and Hearing in Communication},
year={1953},
publisher={Robert E. Krieger Publishing Company},
address={Huntington, New York},
note_={Reprinted in 1958,61,65,72} }

@article{Fletcher53a,
author={Fletcher, Harvey},
title={Stereophonic recording and reproducing system},
journal={Jol. of SMPTE},
year={1953},
month=sep,
volume={61},
number={3},
pages={355-364},
note_={Republished version of \cite{Fletcher34c}.} }

@article{Fletcher54,
author={Fletcher, Harvey},
title={Hearing aid design for selective fitting},
journal={Audecible},
year={1954},
month=nov,
volume={3},
number={6},
pages={11--15},
note_={Interesting discussion from the floor.} }

@inproceedings{Fletcher58,
author={Fletcher, Harvey},
booktitle={Book title unknown},
title={Science and your faith in {G}od},
volume={},
year={1958},
editor={Fletcher, H. and others},
pages={},
publisher={Bookcraft Inc.},
address={},
note_={ } }

@book{Fletcher61,
author={Fletcher, Harvey},
title={The Good Life},
year={1961},
publisher={Deseret Sunday School Union},
address={50 North Main Street, Salt Lake City, UT},
note_={For the Sunday Schools of The Church of Jesus Christ of
Latter-day Saints.} }

@article{Fletcher62,
author={Fletcher, Harvey and Blackham, E.D. and Stratton, R.},
title={Quality of piano tones},
journal=JASA,
year={1962},
month=jun,
volume={34},
number={},
pages={749--61},
note_={} }

@article{Fletcher63a,
author={Fletcher, Harvey and Blackham, E.D. and Christensen, D.A.},
title={Quality of organ tones},
journal=JASA,
year={1963},
month=mar,
volume={35},
number={},
pages={314--25},
note_={} }

@article{Fletcher64,
author={Fletcher, Harvey },
title={Normal vibration frequencies of a stiff piano string},
journal=JASA,
year={1964},
month=mar,
volume={36},
number={},
pages={203--9},
note_={} }

@article{Fletcher65,
author={Fletcher, Harvey and Blackham, E.D. and Geertsen, C.N. },
title={Quality of violin, viola, cello, and bass viol tones, {I}},
journal=JASA,
year={1965},
month=may,
volume={37},
number={5},
pages={851--63},
note_={} }

@book{Fletcher67,
author={Fletcher, Harvey},
title={History of Harvey Fletcher, written by him for his children},
year={1967},
publisher={Unpublished},
note_={Detailed personal stories of HF's life. More than 100 pages.} }

@article{Fletcher67b,
author={Fletcher, Harvey and Saunders, L.C.},
title={Quality of violin vibrato tones},
journal=JASA,
year={1967},
volume={41},
number={},
pages={1534},
note_={} }

@article{Fletcher78a,
author={Fletcher, Harvey and Bassett, I.G.},
title={Some experiments with the bass drum},
journal=JASA,
year={1978},
volume={64},
number={},
pages={1570--76},
note_={} }

@article{oildrop,
author={Fletcher, Harvey},
title={My work with {M}illikan on the oil-drop experiment},
journal={Physics Today},
year={1982},
month=jun,
volume={36},
number={},
pages={43--47},
note_={Fletcher's experience in 1909.
Provided by {M}ark {G}ardner of Spanish Fork UT from Fletcher's
unpublished biography \cite{Fletcher67}; See also
Obituary in {\em Physics Today,} p.\ 116 (Strong, 1981). }}

@incollection{Fletcher95,
author={Fletcher, Harvey},
title={Speech and Hearing in Communication},
booktitle={The ASA edition of Speech and Hearing in Communication},
publisher={Acoustical Society of America},
year={1995},
editor={Jont B. Allen},
address={New York},
note_={Revised edition of Fletcher's 1953 book with corrections and notes,
an extended preface, and a complete bibliography of Fletcher's work
(i.e., this volume).} }