@article{2521, author = {Magill, Kenneth D. jr.}, title = {Subgroups of semigroups of functions}, journal = {Portugaliae mathematica}, volume = {26}, year = {1967}, pages = {133-147}, zbl = {0174.04404}, mrnumber = {0263057}, language = {en}, url = {http://dml.mathdoc.fr/item/2521} }
Magill, Kenneth D. jr. Subgroups of semigroups of functions. Portugaliae mathematica, Tome 26 (1967) pp. 133-147. http://gdmltest.u-ga.fr/item/2521/