Bellamy, J. C. (2003). Digital Telephony (3rd ed.). Wiley India.
Chicago-čujuhus (17. p.)Bellamy, John C. Digital Telephony. 3rd ed. New Dehli: Wiley India, 2003.
MLA-čujuhus (9. p.)Bellamy, John C. Digital Telephony. 3rd ed. Wiley India, 2003.
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