Useful Numerical Constants of Speech and Hearing
Harvey Fletcher · Bell System Technical Journal · 1925
Note: The material given in this paper was prepared in a more condensed form for publication in the International Critical Tables. In order to make it available in convenient form for the use of telephone engineers it was deemed advisable to publish it in this journal. The author is indebted to Dr. J. C. Steinberg for able assistance in collecting and arranging the material.