@inproceedings{PODS-1996-PapadimitriouSV,
	author        = "Christos H. Papadimitriou and Dan Suciu and Victor Vianu",
	booktitle     = "{Proceedings of the 15th Symposium on Principles of Database Systems}",
	doi           = "10.1145/237661.237683",
	isbn          = "0-89791-781-2",
	pages         = "81--92",
	publisher     = "{ACM Press}",
	title         = "{Topological Queries in Spatial Databases}",
	year          = 1996,
}