@article{CMJ_2007__57_1_a19,
     author = {Jakub{\'\i}k, J\'an},
     title = {On idempotent modifications of $MV$-algebras},
     journal = {Czechoslovak Mathematical Journal},
     pages = {243--252},
     publisher = {mathdoc},
     volume = {57},
     number = {1},
     year = {2007},
     mrnumber = {2309963},
     zbl = {1174.06317},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMJ_2007__57_1_a19/}
}