@inproceedings{JICSCP-1988-Levi88,
	author        = "Giorgio Levi",
	booktitle     = "{Proceedings of the Joint International Fifth Conference and Symposium on Logic Programming, 2 Volumes}",
	isbn          = "0-262-61056-6",
	pages         = "1649--1665",
	publisher     = "{MIT Press}",
	title         = "{Models, Unfolding Rules and Fixpoint Semantics}",
	year          = 1988,
}