@article{GDZPPN002249693, title = {Ueber h\"ohere r\"aumliche Nullsysteme.}, journal = {Mathematische Annalen}, volume = {27}, year = {1886}, pages = {277-283}, zbl = {18.0541.02}, url = {http://dml.mathdoc.fr/item/GDZPPN002249693} }
Sturm. Ueber höhere räumliche Nullsysteme.. Mathematische Annalen, Tome 27 (1886) pp. 277-283. http://gdmltest.u-ga.fr/item/GDZPPN002249693/