@article{10_21136_CMJ_1994_128467,
     author = {Fabrici, Imrich},
     title = {$\cal J$-classes in the direct product of two semigroups},
     journal = {Czechoslovak Mathematical Journal},
     pages = {325--335},
     publisher = {mathdoc},
     volume = {44},
     number = {2},
     year = {1994},
     doi = {10.21136/CMJ.1994.128467},
     mrnumber = {1281027},
     zbl = {0836.20086},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/CMJ.1994.128467/}
}