Potter, Ralph Kimball,  1894- <br/><br/>
Visible speech / 
[by] Ralph K. Potter, George A. Kopp and Harriet C. Green. 
 - 1st ed. 
 - New York :  D. Van Nostrand Co.,  1947. 
 - xvi, 441 p. :  ill. ;  28 cm. 
 - Bell Telephone Laboratories series .
 - Bell Telephone Laboratories series. .
<br/><br/>Includes Bibliography and index 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Telephone--Equipment and supplies.
<br/><br/><label>Dewey Class. No.: </label>621.386  / POV 1947