David Pearce Axel Polleres Agustín Valverde Stefan Woltran Proceedings of the LPNMR'07 Workshop on Correspondence and Equivalence for Nonmonotonic Theories (CENT2007), Tempe, AZ, May 14, 2007 CENT CEUR-WS.org CEUR Workshop Proceedings 265 2007 db/conf/lpnmr/cent2007.html