@article{GDZPPN001247964, title = {Decomposition and complexity of finite semigroups.}, journal = {Semigroup forum}, volume = {2}, year = {1971}, pages = {189-250}, zbl = {0226.20060}, url = {http://dml.mathdoc.fr/item/GDZPPN001247964} }
Tilson, B. Decomposition and complexity of finite semigroups.. Semigroup forum, Tome 2 (1971) pp. 189-250. http://gdmltest.u-ga.fr/item/GDZPPN001247964/