فهرست نشریات علمی دسترسی آزاد ایران

We show that there is a one-to-one correspondence (up to isomorphism) between maximal subgroups of a Clifford semigroup and isotropy subgroups of its universal groupoid. We prove that a Clifford semigroup is a union of amenable subgroups if and only if its universal groupoid is amenable. We give an example of an amenable Clifford semigroup that its universal groupoid is not amenable.