APA (7th ed.) Zitazioa
Porter, T. (2006). Practical VoIP Security. Syngress Publishing.
Chicago Style (17th ed.) Zitazioa
Porter, Thomas. Practical VoIP Security. Rockland, MA: Syngress Publishing, 2006.
MLA (9th ed.) Zitazioa
Porter, Thomas. Practical VoIP Security. Syngress Publishing, 2006.
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