@inproceedings{ICLP-1987-Pereira87,
	author        = "Fernando C. N. Pereira",
	booktitle     = "{Proceedings of the Fourth International Conference on Logic Programming, 2 Volumes}",
	isbn          = "0-262-12125-5",
	pages         = "989--1013",
	publisher     = "{MIT Press}",
	title         = "{Grammars and Logics of Partial Information}",
	year          = 1987,
}