Bart Demoen Maria J. García de la Banda Warwick Harvey Kim Marriott David Overton Peter J. Stuckey Herbrand Constraints in HAL. 499-538 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3049&spage=499 2004 conf/lopstr/2004lncs Program Development in Computational Logic db/conf/lopstr/lncs3049.html#DemoenBHMOS04