@inproceedings{KR-1992-Lakemeyer,
	author        = "Gerhard Lakemeyer",
	booktitle     = "{Proceedings of the Third International Conference on Principles of Knowledge Representation and Reasoning}",
	isbn          = "1-55860-262-3",
	pages         = "639--648",
	publisher     = "{Morgan Kaufmann}",
	title         = "{All You Ever Wanted to Know about Tweety (But Were Afraid to Ask)}",
	year          = 1992,
}