@article{MAN_1903__57_158095,
     author = {Friedrich Schur},
     title = {Zur {Proportionslehre.} {(Mit} 3 {Figuren} im {Text)}},
     journal = {Mathematische Annalen},
     pages = {205--208},
     publisher = {mathdoc},
     volume = {57},
     year = {1903},
     url = {http://geodesic.mathdoc.fr/item/MAN_1903__57_158095/}
}