@article{MAN_1931__105_159539,
     author = {U. Wegner},
     title = {Zur {Theorie} der linearen {Differentalgleichungen}},
     journal = {Mathematische Annalen},
     pages = {786--789},
     publisher = {mathdoc},
     volume = {105},
     year = {1931},
     zbl = {57.0512.01},
     url = {http://geodesic.mathdoc.fr/item/MAN_1931__105_159539/}
}