In: Bärbel Mertsching; Marcus Hund; Muhammad Zaheer Aziz (Hrsg.). Proceedings of the 32nd Annual German Conference on Artifical Intelligence. German Conference on Artificial Intelligence (KI-2009), September 15-18, Paderborn, Germany, Pages 452-459, Lecture Notes in Computer Science (LNCS), Vol. 5803, ISBN 978-3-642-04616-2, Springer, Berlin, Heidelberg, 2009.