1. Fuzzy sets as a basis for a theory of possibility;Zadeh;Fuzzy Sets Syst.,1978
2. The Blue and Brown books;Wittgenstein,1958
3. Topologie et linguistique;Thom,1970
4. Structural Stability and Morphogenesis;Thom,1988
5. Archetypal dynamics in word semantics: an application of catastrophe theory;Wildgen,1981