1. A. Avron. Natural 3-valued logics—characterization and proof theory. Journal of Symbolic Logic, 56 (1): 276–294, 1991.
2. M. Baaz and C. G. Fermüller. Nonelementary speedups between different versions of tableaux. In Peter Baumgartner, Reiner Hähnle, and Joachim Posegga, editors, Proc. 4th Workshop on Deduction with Tableaux and Related Methods, St. Goar, Germany, volume 918 of LNCS, pages 217–230. Springer-Verlag, 1995.
3. M. Baaz and C. G. Fermüller. Resolution-based theorem proving for many-valued logics. Journal of Symbolic Computation, 19 (4): 353–391, April 1995.
4. M. Baaz and R. Zach. Note on calculi for a three-valued logic for logic programming. Bulletin of the EATCS, 48: 157–164, 1992.
5. B. Becker and R. Drechsler. Efficient graph-based representation of multi-valued functions with an application to genetic algorithms. In Proc. 24th International Sym- posium on Multiple-Valued Logic, Boston/MA, pages 65–72. IEEE Press, Los Alamitos, May 1994.