@article{SF_1972__4_133890,
     author = {T. Tamura and H.B. Hamilton},
     title = {Is minimal group congruence smallest?},
     journal = {Semigroup forum},
     pages = {173--176},
     publisher = {mathdoc},
     volume = {4},
     year = {1972},
     zbl = {0256.20080},
     url = {http://geodesic.mathdoc.fr/item/SF_1972__4_133890/}
}