a1 Department of Mathematics, University of York, Heslington, York Y01 5DD
In this paper we shall extend the classical theory of Morita equivalence to semigroups with local units. We shall use the concept of a Morita context to rediscover the Rees theorem and to characterise completely 0-simple and regular bisimple semigroups.
(Received May 05 1992)
(Revised June 16 1993)
1991 Mathematics subject classification (Amer. Math. Soc)