1. S.S. Al-Fedaghi, An entity–relationship approach to modelling petroleum engineering database, in: [15], pp. 761–779.
2. A. Badia, Extending entity–relationship models with higher-order operators, in: [64], pp. 321–330.
3. Enhancing the ER model with integrity methods;Balaban;Journal of Database Management,1999
4. CASE*Method: Entity–Relationship Modelling;Barker,1990
5. Entity–Relationship Approach: A Bridge to the User,1989