Homomorphisms and congruences on ωα-bisimple semigroups
J. W. Hogan · Journal of the Australian Mathematical Society · 1973
LetSbe a bisimple semigroup, letEsdenote the set of idempotents ofS, and let ≦ denote the natural partial order relation onEs. Let ≤ * denote the inverse of ≦. The idempotents ofSare said to be well-ordered if (Es, ≦ *) is a well-ordered set.