Klaus Becker Gerd Stumme Rudolf Wille Uta Wille Monika Zickwolff Conceptual Information Systems Discussed through in IT-Security Tool. 352-365 http://link.springer.de/link/service/series/0558/bibs/1937/19370352.htm 2000 conf/ekaw/2000 EKAW db/conf/ekaw/ekaw2000.html#BeckerSWWZ00