@article{SF_1991__43_3_135090,
     author = {J.I. Garcia},
     title = {The congruence extension property for algebraic semigroups.},
     journal = {Semigroup forum},
     pages = {1--18},
     year = {1991},
     volume = {43},
     number = {3},
     zbl = {0728.20052},
     url = {http://geodesic.mathdoc.fr/item/SF_1991__43_3_135090/}
}