1. Tightening the net: a review of current and next generation spam filtering tools, Department of Computer Science and Software Engineering, University of Canterbury, Christchurch;James Carpinter;New Zealand Computers & Security,2006
2. CipherTrust, Inc., Controlling Spam The IronMail® Way, June 2004, (accessed January 2008).
3. Learning spam: simple techniques for freely-available software;Bart,2003
4. “A Fight to Ban Cellphone Spam,” WiredNews;Elisa Batista,2000
5. Natural language processing Laboratory Institute of Computer Software & Theory Northeastern University, an evaluation of statistical spam filtering techniques;Le Zhang;ACM Transactions on Asian Language Information Processing,2004