@article{GDZPPN001264044, title = {Solvable word problems in semigroups.}, journal = {Semigroup forum}, volume = {51}, year = {1995}, pages = {243-246}, zbl = {0821.20040}, url = {http://dml.mathdoc.fr/item/GDZPPN001264044} }
Goldstein, R.Z.; Cummings, P.A. Solvable word problems in semigroups.. Semigroup forum, Tome 51 (1995) pp. 243-246. http://gdmltest.u-ga.fr/item/GDZPPN001264044/