A History of engineering and science in the Bell System / 
prepared by members of the technical staff, Bell Telephone Laboratories ; M.D. Fagen, editor. 
 - [New York] :  The Laboratories,  1975-<c1985   > 
 - v. <1-7   > :  ill. ;  25 cm. 
<br/><br/> Vol. 3 prepared by A.E. Joel, Jr. and other members of the technical staff, Bell Telephone Laboratories; G.E. Schindler, Jr., editor. 
<br/><br/><label>ISBN: </label>0932764002 (v. 2) 
<br/><br/><label>LCCN: </label>75031499  
<br/><br/><label>LC Class. No.: </label>TK6023  / .H57 1975 
<br/><br/><label>Dewey Class. No.: </label>621.385/0973