@inproceedings{KR-1994-CalvaneseLN,
	author        = "Diego Calvanese and Maurizio Lenzerini and Daniele Nardi",
	booktitle     = "{Proceedings of the Fourth International Conference on Principles of Knowledge Representation and Reasoning}",
	isbn          = "1-55860-328-X",
	pages         = "109--120",
	publisher     = "{Morgan Kaufmann}",
	title         = "{A Unified Framework for Class-Based Representation Formalisms}",
	year          = 1994,
}