1. Nonmonotonic reasoning in the framework of situation calculus;Baker;Artificial Intelligence,1991
2. Knowledge representation, reasoning and declarative problem solving;Baral,2003
3. Negation as failure;Clark,1978
4. A planning system for robot construction tasks;Fahlman;Artificial Intelligence,1974
5. STRIPS: A new approach to the application of theorem proving to problem solving;Fikes;Artificial Intelligence,1971