@article{MAN_1886__28_157252,
     author = {Sturm},
     title = {Ueber h\"ohere r\"aumliche {Nullsysteme.}},
     journal = {Mathematische Annalen},
     pages = {277--283},
     publisher = {mathdoc},
     volume = {28},
     year = {1886},
     zbl = {18.0541.02},
     url = {http://geodesic.mathdoc.fr/item/MAN_1886__28_157252/}
}