@inproceedings{IWPTS-1991-Hogrefe91a,
	author        = "Dieter Hogrefe",
	booktitle     = "{Proceedings of the Fourth International Workshop on Protocol Test Systems}",
	isbn          = "0-444-89517-5",
	pages         = "289--290",
	publisher     = "{North-Holland}",
	series        = "{IFIP Transactions}",
	title         = "{Session on Conformance Requirements and Test Purposes in the Context of Formal Methods}",
	volume        = "C-3",
	year          = 1991,
}