@article{GDZPPN002074494,
title = {Ungel\"oste Probleme.},
journal = {Elemente der Mathematik},
volume = {14},
year = {1959},
pages = {82-83},
url = {http://dml.mathdoc.fr/item/GDZPPN002074494}
}
Hadwiger, H. Ungelöste Probleme.. Elemente der Mathematik, Tome 14 (1959) pp. 82-83. http://gdmltest.u-ga.fr/item/GDZPPN002074494/