@article{CMJ_2004__54_1_a19,
     author = {Je\v{z}ek, J.},
     title = {A note on idempotent modifications of groups},
     journal = {Czechoslovak Mathematical Journal},
     pages = {229--231},
     publisher = {mathdoc},
     volume = {54},
     number = {1},
     year = {2004},
     mrnumber = {2040234},
     zbl = {1048.08005},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMJ_2004__54_1_a19/}
}