@inproceedings {4967,
	title = {Concept Projection in Algebras for Computing Certain Answer Descriptions},
	booktitle = {International Workshop on Description Logics (DL)},
	year = {2009},
	url = {http://ceur-ws.org/Vol-477/paper_44.pdf},
	author = {Jeffrey Pound and David Toman and Grant Weddell and Jiewen Wu}
}
