[1] D. Dubois, H. Prade: Fuzzy numbers: an overview. In: Analysis of Fuzzy Information (J.C. Bezdek, ed.), CRC Press, Boca Raton 1988, Vol. 1, pp. 3-39. MR 0910312

[2] M. Mareš: Addition of fuzzy quantities: disjunction-conjunction approach. Kybernetika 25 (1989), 2, 104-116. MR 0995953

[3] M. Mareš: Space of symmetric normal fuzzy quantities. International J. Gen. Systems, submitted.

[4] M. Mareš: Multiplication of fuzzy quantities. Kybernetika 25 (1992), 5, 337-356. MR 1197719

[5] M. Mareš: Additive decomposition of fuzzy quantities with finite supports. Fuzzy Sets and Systems. 47 (1992), 3, 341-346. MR 1166282

[6] M. Mareš: Algebraic equivalences over fuzzy quantities. Kybernetika 29 (1993), 2, 121-132. MR 1227746

[7] M. Mareš: Some remarks to fuzzy CPM. Ekonomicko-matematicky obzor 27(1991), 4, 367-370.

[8] G. J. Klir, T. A. Folger: Fuzzy Sets, Uncertainty, and Information. Prentice Hall, Englewood Cliffs - London 1988. MR 0930102 | Zbl 0675.94025