Dugerdil, P. "Inheritance Mechanisms in the OBJLOG Language: Multiple Selective and Multiple Vertical with Points of View"

M. Lenzerini and D. Nardi and M. Simi (1991) M. Lenzerini and D. Nardi and M. Simi "Inheritance Hierarchies in Knowledge Representation and Programming Languages" Wiley, Chichester, 1991  

Languages mentioned Objlog {1987}