@article{VLDB-2011-OrsiP,
	author        = "Giorgio Orsi and Andreas Pieris",
	ee            = "http://www.vldb.org/pvldb/vol4/p1004-orsi.pdf",
	journal       = "{Proceedings of the VLDB Endowment}",
	number        = 11,
	pages         = "1004--1015",
	title         = "{Optimizing Query Answering under Ontological Constraints}",
	volume        = 4,
	year          = 2011,
}