Quasi-ideals and Type A Semigroups
Chunhua Li · Journal of East China Jiaotong University · 2005
In this paper,we study abundant quasi-ideals on typeA semigroups.We prove that there exists an idempotent-separated good congruence on an abundant quasi-ideal of a type-A semigroup S,which can be extended to an idempotent-separated good congruence on S.