@article{GDZPPN001252941,
title = {On groups of units in a special class of monoids.},
journal = {Semigroup forum},
volume = {16},
year = {1978},
pages = {443-454},
zbl = {0398.20061},
url = {http://dml.mathdoc.fr/item/GDZPPN001252941}
}
Demlová, M. On groups of units in a special class of monoids.. Semigroup forum, Tome 16 (1978) pp. 443-454. http://gdmltest.u-ga.fr/item/GDZPPN001252941/