@article{10_21136_CMJ_1994_128453,
     author = {Chronowski, Antoni},
     title = {Some properties of $\alpha$-ideals and generalized $\alpha$-ideals, $n$-semigroups and $n$-groups},
     journal = {Czechoslovak Mathematical Journal},
     pages = {39--46},
     year = {1994},
     volume = {44},
     number = {1},
     doi = {10.21136/CMJ.1994.128453},
     mrnumber = {1257934},
     zbl = {0814.20058},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/CMJ.1994.128453/}
}