Hagen Höpfner Stefan Conrad Proceedings of the Studierendenprogramm at the 12th GI-conference on Database Systems in Business, Technology and Web, Aachen, March 6, 2007 BTW Studierendenprogramm International University, Bruchsal, Germany 2007 db/conf/btw/btw2007stud.html http://i-u.gky01.punkt.de/index.php?id=521