@article{GDZPPN001251740, title = {Globally Abelian transformation semigroups.}, journal = {Semigroup forum}, volume = {12}, year = {1976}, pages = {221-228}, zbl = {0353.20054}, url = {http://dml.mathdoc.fr/item/GDZPPN001251740} }
Rankin, S.A.; Reis, C.M.; Wang, M.L. Globally Abelian transformation semigroups.. Semigroup forum, Tome 12 (1976) pp. 221-228. http://gdmltest.u-ga.fr/item/GDZPPN001251740/