@article{GDZPPN001259113, title = {Monoids characterized by their quasi-injective S-systems.}, journal = {Semigroup forum}, volume = {36}, year = {1987}, pages = {285-292}, zbl = {0625.20057}, url = {http://dml.mathdoc.fr/item/GDZPPN001259113} }
Ahsan, J. Monoids characterized by their quasi-injective S-systems.. Semigroup forum, Tome 36 (1987) pp. 285-292. http://gdmltest.u-ga.fr/item/GDZPPN001259113/