@article{GDZPPN001256637, title = {Finitely generated left commutative semigroups are residually finite.}, journal = {Semigroup forum}, volume = {30}, year = {1984}, pages = {347-354}, zbl = {0525.20046}, url = {http://dml.mathdoc.fr/item/GDZPPN001256637} }
Nordahl, T. Finitely generated left commutative semigroups are residually finite.. Semigroup forum, Tome 30 (1984) pp. 347-354. http://gdmltest.u-ga.fr/item/GDZPPN001256637/