@article{AUCMP_1989_30_2_a8,
     author = {Hamhalter, Jan},
     title = {The sums of closed subspaces in a topological linear space},
     journal = {Acta Universitatis Carolinae. Mathematica et Physica},
     pages = {61--64},
     year = {1989},
     volume = {30},
     number = {2},
     mrnumber = {1046447},
     zbl = {0715.46001},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/AUCMP_1989_30_2_a8/}
}