Fuzzification of Suzumura's results on choice functions

In this paper, we mainly fuzzify the rationality conditions of choice functions employed by Suzumura and investigate their relationships systematically under the assumption that every involved choice set is normal. We prove that the rationality condition FRR is equivalent to WFCA, and furthermore, that both conditions are equivalent to WAFRP under a strong De Morgan triple. As a consequence, some work done by Suzumura is generalized.