The concept of fuzzy sets was introduced by L. A. Zadeh in 1965. The concept of fuzzy graph was introduced by A. Rosenfeld  in 1975. Many of the crisp graph concepts have been extended to fuzzy graph theory. Here we define the fusion of two vertices in a fuzzy graph and investigate some properties and also give fusion algorithm for effective connectedness and for adjacency matrix.
"A Note on the Fusion of Two Vertices in a Fuzzy Graph." Tsukuba J. Math. 32 (1) 155 - 164, June 2008. https://doi.org/10.21099/tkbjm/1496165195