@article{10_21136_CMJ_1963_100564,
     author = {Schwarz, \v{S}tefan},
     title = {Subsemigroups of simple semigroups},
     journal = {Czechoslovak Mathematical Journal},
     pages = {226--239},
     publisher = {mathdoc},
     volume = {13},
     number = {2},
     year = {1963},
     doi = {10.21136/CMJ.1963.100564},
     mrnumber = {0158014},
     zbl = {0122.02402},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/CMJ.1963.100564/}
}