@inproceedings{ILPS-1997-ZhangF,
	author        = "Yan Zhang and Norman Y. Foo",
	booktitle     = "{Proceedings of the International Symposium on Logic Programming}",
	isbn          = "0-262-63180-6",
	pages         = "69--83",
	publisher     = "{MIT Press}",
	title         = "{Answer Sets for Prioritized Logic Programs}",
	year          = 1997,
}