BIS ’99 3rd International Conference on Business Information Systems, Poznan, Poland 14-16 April 1999 Abramowicz Witold Heftet / 1999 / Engelsk
BIS 2000 4th International Conference on Business Information Systems, Pozna?, Poland, 12–13 April 2000 Abramowicz Witold Heftet / 2000 / Engelsk
OOIS’97 1997 International Conference on Object Oriented Information Systems 10–12 November 1997, Brisbane Proceedings Orlowska Maria E. Heftet / 1997 / Engelsk
