Hobbs, Marvin
Modern communications switching systems
Tab Books, 1981
 Buku Teks SO
Krause, Richard
Motor-uniselectors with noble-metal contacts in telephone switching systems
Van Nostrand Reinhold , 1970
 Buku Teks SO
Smith, Sydney F.
Telephony and telegraphy : and introduction to instruments and switching systems (electromechanical and reed-electronic)
Oxford University Press, 1978
 Buku Teks
Electronic switching : digital central office systems of the world
edited by Amos E. Joel, Jr.
IEEE Press : Sole Worldwide distributor, J. Wiley, 1982
 Buku Teks SO
Roman, Murray
Telephone marketing
McGraw-Hill, 1976
 Buku Teks SO