Cita APA (7a ed.)

Sauer, T., & Wallace, K. (2011). CCNP Voice CVoice 642-437: Quick reference. Cisco Press.

Cita Chicago Style (17a ed.)

Sauer, Toby, y Kevin Wallace. CCNP Voice CVoice 642-437: Quick Reference. Indianapolis, Ind.: Cisco Press, 2011.

Cita MLA (8a ed.)

Sauer, Toby, y Kevin Wallace. CCNP Voice CVoice 642-437: Quick Reference. Cisco Press, 2011.