Alfonso Gerevini Alessandro Saetti Ivan Serina On Managing Temporal Information for Handling Durative Actions in LPG. 91-104 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=2829&spage=91 2003 conf/aiia/2003 AI*IA db/conf/aiia/aiia2003.html#GereviniSS03