@article{MZ_1970__113_171277,
     author = {Alfred L. Foster},
     title = {Congruence {Relations} and {Functional} {Completeness} in {Universal} {Algebras;} {Structure} {Theory} of {Hemi-Primals,} {I.}},
     journal = {Mathematische Zeitschrift},
     pages = {293--308},
     publisher = {mathdoc},
     volume = {113},
     year = {1970},
     zbl = {0181.02301},
     url = {http://geodesic.mathdoc.fr/item/MZ_1970__113_171277/}
}