@article{GDZPPN001261274, title = {Another semigroup of complexity n-1.}, journal = {Semigroup forum}, volume = {43}, year = {1991}, pages = {257-259}, zbl = {0737.20028}, url = {http://dml.mathdoc.fr/item/GDZPPN001261274} }
Foster, A. Another semigroup of complexity n-1.. Semigroup forum, Tome 43 (1991) pp. 257-259. http://gdmltest.u-ga.fr/item/GDZPPN001261274/