@article{MAN_1877__12_156779,
     author = {Sturm},
     title = {Ueber correlative oder reciproke {B\"undel.}},
     journal = {Mathematische Annalen},
     pages = {254--368},
     publisher = {mathdoc},
     volume = {12},
     year = {1877},
     language = {de},
     url = {http://geodesic.mathdoc.fr/item/MAN_1877__12_156779/}
}