Product structure of the fuzzy factor groups (Q1319445)

Fuzzy quotient groups were first examined by \textit{D. H. Foster} [J. Math. Anal. Appl. 67, 549-564 (1979; Zbl 0409.22001)] and \textit{N. P. Mukherjee, P. Bhattacharya} [Inf. Sci. 34, 225-239 (1984; Zbl 0568.20002)]. Recently many authors add new properties [cf. \textit{R. Kumar}, Fuzzy Sets Syst. 48, 267-274 (1992; Zbl 0798.20065); \textit{D. S. Malik, J. N. Mordeson, P. S. Nair}, J. Korean Math. Soc. 29, 1-8 (1992; Zbl 0776.20026); \textit{N. Ajmal, A. S. Prajapati}, Inf. Sci. 64, 17-25 (1992; Zbl 0779.20041)]. This paper deals with fuzzy quotients for fuzzy groups with ``sup property'' [cf. \textit{A. Rosenfeld}, J. Math. Anal. Appl. 35, 512-517 (1971; Zbl 0194.055)]. Some properties of subgroup products are presented. The authors neglect the fact that the ``sup property'' is not necessary in a consideration of quotient fuzzy groups [cf. \textit{I. J. Kumar, P. K. Saxena, P. Yadav}, Fuzzy Sets Syst. 46, 121-132 (1992; Zbl 0776.20025)].