1. Luitzen Egbertus Jan Brouwer. Über die Bedeutung des Satzes vom ausgeschlossenen Dritten in der Mathematik, insbesondere in der Funktiontheorie. Journal für die reine und angewandte Mathematik, 154:1–7, 1923.
2. Keith Clark. Negation as failure. In Herve Gallaire and Jack Minker, editors, Logic and Data Bases, pages 293–322. Plenum Press, New York, 1978.
3. Esra Erdem and Vladimir Lifschitz. Fages’ theorem for programs with nested expressions. In Proceedings of International Conference on Logic Programming (ICLP), pages 242–254, 2001.
4. Esra Erdem and Vladimir Lifschitz. Tight logic programs. Theory and Practice of Logic Programming, 3:499–518, 2003.
5. François Fages. Consistency of Clark’s completion and existence of stable models. Journal of Methods of Logic in Computer Science, 1:51–60, 1994.