@inproceedings{ICLP-1991-PereiraAA,
	author        = "Luís Moniz Pereira and Joaquim Nunes Aparício and José Júlio Alferes",
	booktitle     = "{Proceedings of the Eighth International Conference on Logic Programming}",
	isbn          = "0-262-56058-5",
	pages         = "475--489",
	publisher     = "{MIT Press}",
	title         = "{Nonmonotonic Reasoning with Well Founded Semantics}",
	year          = 1991,
}