Cita APA (7a ed.)

Schmidt, C. A., & Friend, E. (2007). IP telephony using CallManager express lab portfolio. Cisco Press.

Cita Chicago Style (17a ed.)

Schmidt, Cheryl A., y Ernie Friend. IP Telephony Using CallManager Express Lab Portfolio. Indianapolis, Ind.: Cisco Press, 2007.

Cita MLA (8a ed.)

Schmidt, Cheryl A., y Ernie Friend. IP Telephony Using CallManager Express Lab Portfolio. Cisco Press, 2007.