Ralf Küsters Ralf Molitor Approximating most specific concepts in description logics with existential restrictions. 47-59 2002 15 AI Commun. 1 http://iospress.metapress.com/openurl.asp?genre=article&issn=0921-7126&volume=15&issue=1&spage=47 db/journals/aicom/aicom15.html#KustersM02