@inproceedings{PLILP-1991-Poetzsch-Heffter,
	author        = "Arnd Poetzsch-Heffter",
	booktitle     = "{Proceedings of the Third International Symposium on Programming Language Implementation and Logic Programming}",
	doi           = "10.1007/3-540-54444-5_88",
	isbn          = "3-540-54444-5",
	pages         = "63--74",
	publisher     = "{Springer-Verlag}",
	series        = "{Lecture Notes in Computer Science}",
	title         = "{Logic-Based Specification of Visibility Rules}",
	volume        = 528,
	year          = 1991,
}