@inproceedings{KR-2008-Delgrande,
	author        = "James P. Delgrande",
	booktitle     = "{Proceedings of the 11th International Conference on Principles of Knowledge Representation and Reasoning}",
	ee            = "http://www.aaai.org/Library/KR/2008/kr08-016.php",
	isbn          = "978-1-57735-384-3",
	pages         = "156--165",
	publisher     = "{AAAI Press}",
	title         = "{Horn Clause Belief Change: Contraction Functions}",
	year          = 2008,
}