Bell System Technical Journal volume XXXV, number 1, January 1956; volume 30 no. 1.
AT&T 1956; pp 1 - 245 inclusive; photographs, diagrams; references.
AT&T 1956; pp 1 - 245 inclusive; photographs, diagrams; references.
Institute of Radio Engineers, October 1960, pages 1693-1820 inclusive; Illustrations, References.
Prepared by Bell Telephone Laboratories, Inc for Western Electric Co, Inc, New York, NY 1951; 792 pages.