Cadoli, M., Donini, F. M., Liberatore, P., & Schaerf, M. (1999). The size of a revised knowledge base. Artificial Intelligence, 115**(1), 25–64.**
Cadoli, M., Donini, F. M., & Schaerf, M. (1995). On compact representations of propositional circumscription. In Proceedings of the Twelfth Symposium on Theoretical Aspects of Computer Science (STACS'95)**, pp. 205–216. Extended version as RAP.14.95**
DIS, Univ. of Roma "La Sapienza", July 1995.

Cadoli, M., Donini, F. M., & Schaerf, M. (1996). Is intractability of non-monotonic reasoning a real drawback?. Artificial Intelligence, 88**(1–2), 215–251.**
Cadoli, M., Donini, F. M., Schaerf, M., & Silvestri, R. (1997). On compact representations of propositional circumscription. Theoretical Computer Science, 182**, 183–202.**
Cook, S. A. (1971). The complexity of theorem-proving procedures. In **Proceedings of the**
Third ACM Symposium on Theory of Computing (STOC'71)**, pp. 151–158.**
Eiter, T., & Gottlob, G. (1992). On the complexity of propositional knowledge base revision, updates and counterfactuals. Artificial Intelligence, 57**, 227–270.**
Eiter, T., & Gottlob, G. (1993). Propositional circumscription and extended closed world reasoning are Πp 2
-complete. Theoretical Computer Science, 114**, 231–245.**
Etherington, D. V. (1987). Reasoning with incomplete information**. Morgan Kaufmann,**
Los Altos, Los Altos, CA.

Fagin, R., Ullman, J. D., & Vardi, M. Y. (1983). On the semantics of updates in databases.

In **Proceedings of the Second ACM SIGACT SIGMOD Symposium on Principles of** Database Systems (PODS'83)**, pp. 352–365.**
Garey, M. R., & Johnson, D. S. (1979). **Computers and Intractability: A Guide to the**
Theory of NP-Completeness**. W.H. Freeman and Company, San Francisco, Ca.**
Gelfond, M., & Lifschitz, V. (1988). The stable model semantics for logic programming.

In Proceedings of the Fifth Logic Programming Symposium**, pp. 1070–1080. The MIT** Press.

Gelfond, M., Przymusinska, H., & Przymusinsky, T. (1989). On the relationship between circumscription and negation as failure. Artificial Intelligence, 38**, 49–73.**
Ginsberg, M. L. (1986). Conterfactuals. Artificial Intelligence, 30**, 35–79.**
Gogic, G., Kautz, H. A., Papadimitriou, C., & Selman, B. (1995). The comparative linguistics of knowledge representation. In **Proceedings of the Fourteenth International**
Joint Conference on Artificial Intelligence (IJCAI'95)**, pp. 862–869.**
Gottlob, G. (1992). Complexity results for nonmonotonic logics. **Journal of Logic and**
Computation, 2**, 397–425.**
Gottlob, G. (1995). Translating default logic into standard autoepistemic logic. **Journal of**
the ACM, 42**, 711–740.**