Rees matrix semigroups
Mark V. Lawson · Proceedings of the Edinburgh Mathematical Society · 1990
In this paper we provide a new, abstract characterisation of classical Rees matrix semigroups over monoids with zero. The corresponding abstract class of semigroups is obtained by abstracting a number of algebraic properties from completely 0-simple semigroups: in particular, the relationship between arbitrary elements and idempotents.