International Conference on Entity-Relationship Approach., & Kangassalo, H. (1991). Entity-relationship approach, the core of conceptual modelling: Proceedings of the Ninth International Conference on the Entity-Relationship Approach, Lausanne, Switzerland, 8-10 October, 1990. Amsterdam: North-Holland.
Παραπομπή Chicago StyleInternational Conference on Entity-Relationship Approach., and Hannu Kangassalo. Entity-relationship Approach, the Core of Conceptual Modelling: Proceedings of the Ninth International Conference On the Entity-Relationship Approach, Lausanne, Switzerland, 8-10 October, 1990. Amsterdam: North-Holland, 1991.
Παραπομπή MLAInternational Conference on Entity-Relationship Approach., and Hannu Kangassalo. Entity-relationship Approach, the Core of Conceptual Modelling: Proceedings of the Ninth International Conference On the Entity-Relationship Approach, Lausanne, Switzerland, 8-10 October, 1990. Amsterdam: North-Holland, 1991.