@article{GDZPPN001254774, title = {Finite globally idempotent semigroups.}, journal = {Semigroup forum}, volume = {23}, year = {1981}, pages = {217-224}, zbl = {0463.20044}, url = {http://dml.mathdoc.fr/item/GDZPPN001254774} }
Grzymala-Busse, J.W. Finite globally idempotent semigroups.. Semigroup forum, Tome 23 (1981) pp. 217-224. http://gdmltest.u-ga.fr/item/GDZPPN001254774/