@article{GDZPPN001253425, title = {On factor S-sets of monoids modulo submonoids.}, journal = {Semigroup forum}, volume = {18}, year = {1979}, pages = {163-172}, zbl = {0419.20049}, url = {http://dml.mathdoc.fr/item/GDZPPN001253425} }
Grassmann, H. On factor S-sets of monoids modulo submonoids.. Semigroup forum, Tome 18 (1979) pp. 163-172. http://gdmltest.u-ga.fr/item/GDZPPN001253425/