Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{SF_1970__1_133782, author = {A.H. Clifford}, title = {Radicals in semigroups.}, journal = {Semigroup forum}, pages = {103--127}, publisher = {mathdoc}, volume = {1}, year = {1970}, zbl = {0209.04801}, url = {http://geodesic.mathdoc.fr/item/SF_1970__1_133782/} }
A.H. Clifford. Radicals in semigroups.. Semigroup forum, Tome 1 (1970), pp. 103-127. http://geodesic.mathdoc.fr/item/SF_1970__1_133782/