@inproceedings{FASE-2001-HeckelS,
	author        = "Reiko Heckel and Stefan Sauer",
	booktitle     = "{Proceedings of the Fourth International Conference on Fundamental Approaches to Software Engineering}",
	doi           = "10.1007/3-540-45314-8_9",
	isbn          = "3-540-41863-6",
	pages         = "109--123",
	publisher     = "{Springer-Verlag}",
	series        = "{Lecture Notes in Computer Science}",
	title         = "{Strengthening UML Collaboration Diagrams by State Transformations}",
	volume        = 2029,
	year          = 2001,
}