@article{CMJ_2003__53_1_a14,
     author = {Bican, Ladislav and Torrecillas, Blas},
     title = {Precovers},
     journal = {Czechoslovak Mathematical Journal},
     pages = {191--203},
     publisher = {mathdoc},
     volume = {53},
     number = {1},
     year = {2003},
     mrnumber = {1962008},
     zbl = {1016.16003},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMJ_2003__53_1_a14/}
}