@article{ELMA_1962__17_140754,
     author = {H. Hadwiger},
     title = {Ungel\"oste {Probleme.}},
     journal = {Elemente der Mathematik},
     pages = {84--85},
     year = {1962},
     volume = {17},
     url = {http://geodesic.mathdoc.fr/item/ELMA_1962__17_140754/}
}