@inproceedings{KR-2002-DeneckerMT,
	author        = "Marc Denecker and V. Wiktor Marek and Miroslaw Truszczynski",
	booktitle     = "{Proceedings of the Eighth International Conference on Principles of Knowledge Representation and Reasoning}",
	isbn          = "1-55860-554-1",
	pages         = "177--190",
	publisher     = "{Morgan Kaufmann}",
	title         = "{Ultimate Approximations in Nonmonotonic Knowledge Representation Systems}",
	year          = 2002,
}