@article{GDZPPN001264311, title = {Varieties of operator semigroups representing partitions.}, journal = {Semigroup forum}, volume = {51}, year = {1995}, pages = {135-152}, zbl = {0835.20079}, url = {http://dml.mathdoc.fr/item/GDZPPN001264311} }
Padmanabhan, R.; Lakser, H.; Wolk, B. Varieties of operator semigroups representing partitions.. Semigroup forum, Tome 51 (1995) pp. 135-152. http://gdmltest.u-ga.fr/item/GDZPPN001264311/