@article{MZ_1940__46_168918,
     author = {H., Graf},
     title = {R\"aumliche {Ebenennetze,} deren {Sechsflachzellen} {Inkugeln} besitzen},
     journal = {Mathematische Zeitschrift},
     pages = {591--604},
     publisher = {mathdoc},
     volume = {46},
     year = {1940},
     zbl = {0023.26004},
     url = {http://geodesic.mathdoc.fr/item/MZ_1940__46_168918/}
}