1. Structuring logic programming: a unifying approach and its declarative and operational semantics;Brogi;Tech. Rept. 4/1,1990
2. N-prolog: an extension of prolog with hypothetical implications;Gabbay;J. Logic Programming,1984
3. The design of an abstract machine for efficient implementation of contexts in logic programming;Lemma,1989
4. Foundations of Logic Programming;Lloyd,1987
5. Clausal intuitionistic logic 1: fixed point semantics;McCarthy;J. Logic Programming,1988