1. Ahre, K.,Locally compact bisimple inverse semigroups, Dissertation, Boğaziçi University, 1978.
2. Bourbaki, N.,General topology I, Addison-Wesley, Reading, Mass. 1966.
3. Mathematical Surveys;A. H. Clifford,1961
4. Dugundji, J.,Topology, Allyn and Bacon, Inc., Boston, 1966.
5. Hofmann, K. H. and P. S. Mostert,Elements of compact semigroups, Charles E. Merrill Books, Inc., Columbus, Ohio, 1966.