@article{CMUC_1971__12_1_a14,
     author = {Trnkov\'a, V\v{e}ra},
     title = {On descriptive classification of set-functors. {I.}},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     pages = {143--174},
     publisher = {mathdoc},
     volume = {12},
     number = {1},
     year = {1971},
     mrnumber = {0294445},
     zbl = {0232.18004},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMUC_1971__12_1_a14/}
}