@article{GDZPPN00126074X, title = {Pseudovarieties of completely regular semigroups.}, journal = {Semigroup forum}, volume = {43}, year = {1991}, pages = {1-46}, zbl = {0719.20031}, url = {http://dml.mathdoc.fr/item/GDZPPN00126074X} }
Pastijn, F. Pseudovarieties of completely regular semigroups.. Semigroup forum, Tome 43 (1991) pp. 1-46. http://gdmltest.u-ga.fr/item/GDZPPN00126074X/