@article{700919,
     title = {The space of mappings into the sphere and its topological applications},
     booktitle = {General Topology and its Relations to Modern Analysis and Algebra},
     series = {GDML\_Books},
     publisher = {Academia Publishing House of the Czechoslovak Academy of Sciences},
     address = {Praha},
     year = {1962},
     pages = {[257]-[257]},
     url = {http://dml.mathdoc.fr/item/700919}
}

Kuratowski, K. The space of mappings into the sphere and its topological applications, dans General Topology and its Relations to Modern Analysis and Algebra, GDML_Books,  (1962), p. [257]. http://gdmltest.u-ga.fr/item/700919/