1. P. Bauer, E. P. Klement, B. Moserand A. Leikermoser. Modeling of Control Functions by Fuzzy Controllers. In: H. T. Nguyen et al.,eds. Theoretical Aspects of Fuzzy Control. J. Wiley and Sons, New York, pp. 91–116,1995.
2. L. Biacino and G. Gerla. Weak Decidability and Weak Recursive Enumerability for L-subsets. Preprint No. 45, Università Degli Studi di Napoli, Napoli 1986.
3. J. J. Buckley and Y. Hayashi. Fuzzy input-output controllers are universal approximators. Fuzzy Sets and Systems, 58, 273–278, 1993.
4. Butnariu and Klement, 19931 D. Butnariu and E. P. Klement. Triangular Norm-based Measures and Games with Fuzzy Coalitions. Kluwer, Dordrecht, 1993.
5. J. Castro. Fuzzy Logic Controllers are Universal Approximators, Techn. Report #DECSAI-93101, University of Granada, 1993.