@inproceedings{CAiSE-1991-Dietz,
	author        = "Jan L. G. Dietz",
	booktitle     = "{Proceedings of the Third Conference on Advanced Information Systems Engineering}",
	doi           = "10.1007/3-540-54059-8_98",
	isbn          = "3-540-54059-8",
	pages         = "441--460",
	publisher     = "{Springer-Verlag}",
	series        = "{Lecture Notes in Computer Science}",
	title         = "{The Essential System Model}",
	volume        = 498,
	year          = 1991,
}