@article{10_1017_S0017089500005656, author = {McFadden, R. B.}, title = {Unit-regular orthodox semigroups}, journal = {Glasgow mathematical journal}, pages = {229--240}, year = {1984}, volume = {25}, number = {2}, doi = {10.1017/S0017089500005656}, url = {http://geodesic.mathdoc.fr/articles/10.1017/S0017089500005656/} }