K. Kuutti. ECSCW'91: Proceedings of the second conference on European Conference on Computer-Supported Cooperative Work, page 249--264. Norwell, MA, USA, Kluwer Academic Publishers, (1991)
M. Dumas, and A. ter Hofstede. In Proc. of the International Conference on the Unified Modeling Language (UML). Toronto, Canada, October 2001. Springer
Verlag., (2001)
W. van der Aalst, A. ter Hofstede, B. Kiepuszewski, and A. Barros. 7th International Conference on Cooperative Information Systems (CoopIS
2000), volume 1901 of Lecture Notes in Computer Science, page 18--29. Springer-Verlag, Berlin, (2000)