Alfonso Gerevini Ugur Kuter Dana S. Nau Alessandro Saetti Nathaniel Waisbrot Combining Domain-Independent Planning and HTN Planning: The Duet Planner. 573-577 2008 ECAI http://dx.doi.org/10.3233/978-1-58603-891-5-573 conf/ecai/2008 db/conf/ecai/ecai2008.html#GereviniKNSW08