PT Unknown AU Cesta, A Finzi, A Fratini, S Orlandini, A Tronci, E TI Flexible Timeline-Based Plan Verification SE KI 2009: Advances in Artificial Intelligence, 32nd Annual German Conference on AI, Paderborn, Germany, September 15-18, 2009. Proceedings PY 2009 BP 49 EP 56 VL 5803 DI 10.1007/978-3-642-04617-9_7 ER