Christian Freksa Michael Kohlhase Kerstin Schill KI 2006: Advances in Artificial Intelligence, 29th Annual German Conference on AI, KI 2006, Bremen, Germany, June 14-17, 2006, Proceedings KI Lecture Notes in Computer Science 4314 Springer 2007 978-3-540-69911-8 db/conf/ki/ki2006.html