[Zadeh L.a.] Fuzzy Sets as a Basic for a Theory of(Bokos-Z1)
Possibility Theory and its applications: a retrospective and prospective view D. Dubois, H. Prade IRIT-CNRS, Université Paul Sabatier 31062 TOULOUSE FRANCE.
International Conference on Fuzzy Systems and Knowledge Discovery, p.p. 103-107,July 2011.