A history of engineering and science in the bell system communications sciences (1925-1980) / 
prepared by members of the technical staff, AT & T Bell Laboratories; editor, M. D. Fagen. 
 - New York :  AT & T Bell Laboratories,  1975. 
 - v. :  ill. ;  23cm. 
<br/><br/><label>ISBN: </label>0932764061 (vol.5) 
<br/><br/><label>LCCN: </label>75-31499 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Telephone--History.--United States<br/>Telecommunication--History.--United States<br/>Electronics--History.--United States<br/>American telephone and telegraph company--History.