@article{CMUC_1969_10_3_a3,
     author = {Luke\v{s}, Jaroslav},
     title = {On the topological extensions},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     pages = {407--420},
     year = {1969},
     volume = {10},
     number = {3},
     mrnumber = {0257980},
     zbl = {0187.44504},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMUC_1969_10_3_a3/}
}