Voir la notice de l'article provenant de la source Czech Digital Mathematics Library
@article{MASLO_1971__21_4_a6, author = {Pond\v{e}l{\'\i}\v{c}ek, Bed\v{r}ich}, title = {A {Note} on {Classes} of {Regularity} in {Semigroups}}, journal = {Mathematica slovaca}, pages = {312--317}, publisher = {mathdoc}, volume = {21}, number = {4}, year = {1971}, mrnumber = {0301122}, zbl = {0235.20057}, language = {en}, url = {http://geodesic.mathdoc.fr/item/MASLO_1971__21_4_a6/} }
Pondělíček, Bedřich. A Note on Classes of Regularity in Semigroups. Mathematica slovaca, Tome 21 (1971) no. 4, pp. 312-317. http://geodesic.mathdoc.fr/item/MASLO_1971__21_4_a6/