@article{GDZPPN00125524X, title = {Smallest A-ideals in semigroups.}, journal = {Semigroup forum}, volume = {23}, year = {1981}, pages = {297-310}, zbl = {0484.20030}, url = {http://dml.mathdoc.fr/item/GDZPPN00125524X} }
Satko, L.; Grosek, O. Smallest A-ideals in semigroups.. Semigroup forum, Tome 23 (1981) pp. 297-310. http://gdmltest.u-ga.fr/item/GDZPPN00125524X/