@article{SF_1991__42_3_135071,
     author = {M.E. Adams and M. Gould and S.T. Tschantz},
     title = {The congruence class of an idempotent in a regular semigroup.},
     journal = {Semigroup forum},
     pages = {121--124},
     publisher = {mathdoc},
     volume = {42},
     number = {3},
     year = {1991},
     zbl = {0741.20047},
     url = {http://geodesic.mathdoc.fr/item/SF_1991__42_3_135071/}
}