Franz Pühretmair Hildegard Rumetshofer Erwin Schaumlechner Extended Decision Making in Tourism Information Systems. 57-66 2002 conf/ecweb/2002 EC-Web http://link.springer.de/link/service/series/0558/bibs/2455/24550057.htm db/conf/ecweb/ecweb2002.html#PuhretmairRS02