1. Sur les opérations definies pour des nombres réels;Aczél;Bull. Soc. Math. France,1949
2. Naturally totally ordered commutative semigroups;Clifford;Amer. J. Math.,1954
3. Sur l’équation fonctionelle de l'associativité;Climescu;Bull. École Polytechn. Iassy,1946
4. R. Mesiar, B. De Baets, New construction methods for aggregation operators, Proc. 8th Internat. Conf. on Information Processing and Management of Uncertainty in Knowledge-Based Systems (Madrid, Spain), Vol. II, 2000, pp. 701–706.
5. Contrapositive symmetry of fuzzy implications;Fodor;Fuzzy Sets and Systems,1995