@article{CMJ_2007_57_1_a28,
     author = {Song, Yan-Kui},
     title = {Spaces with large relative extent},
     journal = {Czechoslovak Mathematical Journal},
     pages = {387--394},
     year = {2007},
     volume = {57},
     number = {1},
     mrnumber = {2309972},
     zbl = {1174.54014},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMJ_2007_57_1_a28/}
}