On Refined Semilattices of Semigroups
Zhengpan Wang, Yuqi Guo, K. P. Shum · Algebra Colloquium · 2008
We give a short proof for the associativity of the binary operation defined on a refined system of semigroups indexed by a semilattice. The main result given by Zhang, Shum and Zhang in 2001 on the refined semilattice of semigroups is substantially strengthened.