@article{10_21136_CMJ_1988_102201,
     author = {Jakub{\'\i}k, J\'an},
     title = {Closure operators on the lattice of radical classes of lattice ordered groups},
     journal = {Czechoslovak Mathematical Journal},
     pages = {71--77},
     publisher = {mathdoc},
     volume = {38},
     number = {1},
     year = {1988},
     doi = {10.21136/CMJ.1988.102201},
     mrnumber = {925941},
     zbl = {0655.06012},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/CMJ.1988.102201/}
}