Biswas, N. (2000). Principles of Telephony. Radient Books.
Chicago Style (17th ed.) ZitazioaBiswas, N.N. Principles of Telephony. India: Radient Books, 2000.
MLA (9th ed.) ZitazioaBiswas, N.N. Principles of Telephony. Radient Books, 2000.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.