@article{MZ_1920__8_167605,
     author = {B., von von Ker\'ekj\'art\'o},
     title = {Zur {Theorie} der mehrdeutigen stetigen {Abbildungen}},
     journal = {Mathematische Zeitschrift},
     pages = {310--319},
     publisher = {mathdoc},
     volume = {8},
     year = {1920},
     zbl = {47.0240.02},
     url = {http://geodesic.mathdoc.fr/item/MZ_1920__8_167605/}
}