@article{GDZPPN001252828,
title = {Radicals of semigroups.},
journal = {Semigroup forum},
volume = {16},
year = {1978},
pages = {299-344},
zbl = {0393.20047},
url = {http://dml.mathdoc.fr/item/GDZPPN001252828}
}
Schein, B.M.; Roiz, E.N. Radicals of semigroups.. Semigroup forum, Tome 16 (1978) pp. 299-344. http://gdmltest.u-ga.fr/item/GDZPPN001252828/