@article{CLTM_2007_2007_1_a4,
     author = {Tyszka, Apoloniusz},
     title = {Elementos {{\O}-definibles} en un campo.},
     journal = {Collectanea mathematica},
     pages = {73-84},
     publisher = {mathdoc},
     volume = {58},
     number = {1},
     year = {2007},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CLTM_2007_2007_1_a4/}
}