Abstract Interpretation: Towards the Global Optimization of Prolog Programs. - Maurice Bruynooghe; Gerda Janssens; Alain Callebaut; Bart Demoen (SLP, 1987)

Indexing Prolog Clauses. - Bart Demoen; André Mariën; Alain Callebaut (NACLP, 1989)

Carmen: A Prolog Tool for Generating User Interfaces. - Alain Callebaut (LPE, 1990)

Program Source as Model for Debugging Prolog. - Alain Callebaut; Bart Demoen (LPE, 1990)