Christine Parent, Hélène Rolin, Kokou Yétongnon, Stefano Spaccapietra. An ER Calculus for the Entity-Relationship Complex Model. In Frederick H. Lochovsky, editor, Entity-Relationship Approach to Database Design and Querying, Proceedings of the Eight International Conference on Enity-Relationship Approach, Toronto, Canada, 18-20 October, 1989. pages 361-384, North-Holland, 1989. [doi]
Abstract is missing.