@inproceedings{ICLP-1995-BoyeM,
	author        = "Johan Boye and Jan Maluszynski",
	booktitle     = "{Proceedings of the 12th International Conference on Logic Programming}",
	isbn          = "0-262-69177-9",
	pages         = "747--761",
	publisher     = "{MIT Press}",
	title         = "{Two Aspects of Directional Types}",
	year          = 1995,
}