@inproceedings{PODS-2002-Lenzerini,
	author        = "Maurizio Lenzerini",
	booktitle     = "{Proceedings of the 21st Symposium on Principles of Database Systems}",
	doi           = "10.1145/543613.543644",
	ee            = "http://www.acm.org/sigs/sigmod/pods/proc02/papers/233-Lenzerini.pdf",
	isbn          = "1-58113-507-6",
	pages         = "233--246",
	publisher     = "{ACM}",
	title         = "{Data Integration: A Theoretical Perspective}",
	year          = 2002,
}