[Black2000] 2000 PPP and L2TP: Remote Access Communications. Upper Saddle River, NJ: Prentice Hall.
[Comer1995] 1995. Internetworking with TCP/IP, Volume 1. Upper Saddle River, NJ: Prentice Hall.
[Doraswamy1999] 1999. IPSec: The New Security Standard for the Internet, Intranets, and Virtual Private Networks. Upper Saddle River, NJ: Prentice Hall.
[Eberspacher2001] 2001. GSM Switching, Services and Protocols. West Sussex, England: Wiley & Sons.
[Garg2002] 2002. Wireless Network Evolution: 2G to 3G. Upper Saddle River, NJ: Prentice Hall.
[Hennessy1996] 1996. Computer Architecture: A Quantitative Approach. San Francisco: Morgan Kaufmann Publishers.
[Kaaranen2001] 2001. UMTS Networks: Architecture, Mobility and Services. West Sussex, England: Wiley & Sons.
[Kotler1999] 2000. Marketing Management. Upper Saddle River, NJ: Prentice Hall.
[Solomon1998] 1998. Mobile IP. Upper Saddle River, NJ: Prentice Hall.
[Yuan2001] 2001. Virtual Private Networks: Technologies and Solutions. Upper Saddle River, NJ: Addison-Wesley.