Salvatore J. Stolfo Shlomo Hershkop Ke Wang Olivier Nimeskern Chia-Wei Hu A Behavior-Based Approach to Securing Email Systems. 57-81 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=2776&spage=57 2003 conf/mmmacns/2003 MMM-ACNS db/conf/mmmacns/mmmacns2003.html#StolfoHWNH03