@article{ELMA_1969__24_140947,
     author = {H. Hadwiger},
     title = {Ungel\"oste {Probleme.}},
     journal = {Elemente der Mathematik},
     pages = {126--128},
     publisher = {mathdoc},
     volume = {24},
     year = {1969},
     url = {http://geodesic.mathdoc.fr/item/ELMA_1969__24_140947/}
}