@article{10_1017_S0017089500002275,
     author = {Pirnot, Thomas L.},
     title = {Certain congruences on a completely regular semigroup},
     journal = {Glasgow mathematical journal},
     pages = {109--120},
     year = {1974},
     volume = {15},
     number = {2},
     doi = {10.1017/S0017089500002275},
     url = {http://geodesic.mathdoc.fr/articles/10.1017/S0017089500002275/}
}