@article{10_21136_CMJ_1971_101032,
     author = {Kim, Jin Bai},
     title = {Mutants in the symmetric semigroups},
     journal = {Czechoslovak Mathematical Journal},
     pages = {355--363},
     publisher = {mathdoc},
     volume = {21},
     number = {3},
     year = {1971},
     doi = {10.21136/CMJ.1971.101032},
     mrnumber = {0292968},
     zbl = {0228.20039},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/CMJ.1971.101032/}
}