1. Foundations of Logic Programming;Lloyd,1987
2. A First Course in Fuzzy Logic;Nguyen,2000
3. Fuzzy logic and the resolution principle;Lee;Journal of the ACM,1972
4. M. Ishizuka, N. Kanai, Prolog-ELF incorporating fuzzy logic, in: A.K. Joshi (Ed.), Proc. 9th Internat. Jt. Conf. on Artificial Intelligence (IJCAI’85), Los Angeles, CA, August 1985, Morgan Kaufmann, Los Altos, CA, 1985, pp. 701–703.
5. Fril, Fuzzy and Evidential Reasoning in Artificial Intelligence;Baldwin,1995