@inproceedings{CAiSE-1999-CalvaneseGL,
	author        = "Diego Calvanese and Giuseppe De Giacomo and Maurizio Lenzerini",
	booktitle     = "{Proceedings of the 11th International Conference on Advanced Information Systems Engineering}",
	doi           = "10.1007/3-540-48738-7_34",
	isbn          = "3-540-66157-3",
	pages         = "434--438",
	publisher     = "{Springer-Verlag}",
	series        = "{Lecture Notes in Computer Science}",
	title         = "{Queries and Constraints on Semi-structured Data}",
	volume        = 1626,
	year          = 1999,
}