A note on fuzzy relations and fuzzy groups (Q2639181)

The paper characterizes groups G such that for any fuzzy subgroup R of \(G\times G\) the formula \(A_ R(x)=\sup_{y\in G}\min (R(x,y),R(y,x))\) gives a fuzzy subgroup of G. This corrects a result of \textit{P. Bhattacharya} and \textit{N. P. Mukherjee} [Inf. Sci. 36, 267-282 (1985; Zbl 0599.20003), Theorem 4.7].