1. Chester , D. L. L. Daniels R. J. Fickelscherer D. H. Lenz 2008
2. “Fuzzy Logic Clarifies Operations,”;Fickelscherer;InTech,2005
3. “Malfunction Diagnosis Using Quantitative Models and Non-Boolean Reasoning in Expert Systems,”;Kramer;AIChE Journal,1987
4. Expert Systems — A Practical Introduction
5. “On Evidential Reasoning in a Hierarchy of Hypotheses,”;Pearl;Artificial Intelligence,1986