Jörg Kahl Lothar Hotz Heiko Milde Stephanie Wessel Improving Reasoning Efficiency for Subclasses of Allen's Algebra with Instantiation Intervals. 299-302 http://link.springer.de/link/service/series/0558/bibs/1701/17010299.htm 1999 conf/ki/1999 KI db/conf/ki/ki99.html#KahlHMW99