Gaya APA

WHITMAN, M, E. et al (2009). Guide to Firewalls and Networks Security : with Intrusion Detection and VPNs (2). USA: Course Technology Cengage Learning.

Gaya MLA

WHITMAN, MICHAEL, E.. et al. "Guide to Firewalls and Networks Security : with Intrusion Detection and VPNs". 2 USA: Course Technology Cengage Learning, 2009. Text.