Maximum idempotents in naturally ordered regular semigroups
D. B. McAlister, R. McFadden · Proceedings of the Edinburgh Mathematical Society · 1983
We shall denote by ω the natural partial order on the idempotents E = E(S) of a regular semigroup S, so that in E, A partially ordered semigroup S(≦) is called naturally partially ordered [9] if the imposed partial order ≦ extends ω in the sense that No assumption is made about the reverse implication.