Thomas W. Reps Shmuel Sagiv Reinhard Wilhelm Static Program Analysis via 3-Valued Logic. 15-30 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3114&spage=15 2004 conf/cav/2004 CAV db/conf/cav/cav2004.html#RepsSW04