@article{ARM_1977__13_2_a7,
     author = {\v{S}marda, Bohumil},
     title = {Polars on closure spaces},
     journal = {Archivum mathematicum},
     pages = {117--124},
     publisher = {mathdoc},
     volume = {13},
     number = {2},
     year = {1977},
     mrnumber = {0460192},
     zbl = {0374.06008},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/ARM_1977__13_2_a7/}
}