1. A Top-Down Derivation Procedure for Programs with Explicit Negation;Alferes,1994
2. Introduction to Logic Programming;Apt,1990
3. Negation by Default and Unstratifiable Logic Programs;Bidoit;J. Theoret. Comput. Sci.,1991
4. Loop Checking and Negation;Bol;J. Logic Programming,1993
5. The Underlying Search for Magic Templates and Tabulation;Bol,1993