@inproceedings{PODS-1990-Lassez,
	author        = "Jean-Louis Lassez",
	booktitle     = "{Proceedings of the Ninth Symposium on Principles of Database Systems}",
	cdrom         = "['journals/anthology/cd1-3:PODS90/P288.PDF', 'journals/anthology/dvd1:text/1-3/PODS90/P288.PDF']",
	doi           = "10.1145/298514.298581",
	isbn          = "0-89791-352-3",
	pages         = "288--298",
	publisher     = "{ACM Press}",
	title         = "{Querying Constraints}",
	year          = 1990,
}