P. Kroha. Database and Expert Systems Applications, Volume 1873 von Lecture Notes in Computer Science, Seite 675-684. Springer Berlin / Heidelberg, (2000)
L. Dawson, und P. Swatman. ICIS '99: Proceeding of the 20th international conference on Information Systems, Seite 260--273. Atlanta, GA, USA, Association for Information Systems, (1999)