A remark concerning -systems
A remark on semigroups that are semilattices of right groups
A uniform chain whose inverse semigroup has no chart.
Absolute flatness of regular semigroups with a finite height function.
Algebra in the superextensions of twinic groups [Book]
Any O-simple dual semigroup is completely O-simple.
Atanassov’s Intuitionistic Fuzzy Ideals of Po--Semigroups