@inproceedings{VLDB-1977-Lipski,
	author        = "Witold Lipski Jr.",
	booktitle     = "{Proceedings of the Third International Conference on Very Large Data Bases}",
	cdrom         = "VLDB77/P491.PDF",
	pages         = "491",
	publisher     = "{IEEE Computer Society}",
	title         = "{On Semantic Issues Connected with Incomplete Information Data Bases}",
	year          = 1977,
}