N. Friedman, and J. Halpern. In Principles of Knowledge Representation and Reasoning: Proc. Fourth International Conference (KR '94), page 202--213. Morgan Kaufmann, (1994)
L., G. V., and P. Giordano. Proceedings of TABLEAUX 2007 (16th International Conference on Automated Reasoning with Analytic Tableaux and Related Methods), volume 4548 of LNAI, page 238--244. Aix En Provence, France, Springer-Verlag, (July 2007)