@article{700857,
     title = {On discontinuous selectors},
     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 = {1967},
     pages = {235-235},
     zbl = {0161.42101},
     url = {http://dml.mathdoc.fr/item/700857}
}

Kuratowski, K. On discontinuous selectors, dans General Topology and its Relations to Modern Analysis and Algebra, GDML_Books,  (1967), p. 235. http://gdmltest.u-ga.fr/item/700857/