Heikki Virtanen Henri Hansen Antti Valmari Juha Nieminen Timo Erkkilä Tampere Verification Tool. 153-157 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=2988&spage=153 2004 conf/tacas/2004 TACAS db/conf/tacas/tacas2004.html#VirtanenHVNE04