@article{MAN_1903__57_158092,
     author = {Werner Boy},
     title = {\"Uber die {Curvatura} integra und die {Topologie} geschlossener {Fl\"achen.} {(Mit} 24 {Figuren} im {Text)}},
     journal = {Mathematische Annalen},
     pages = {151--184},
     publisher = {mathdoc},
     volume = {57},
     year = {1903},
     zbl = {34.0537.07},
     url = {http://geodesic.mathdoc.fr/item/MAN_1903__57_158092/}
}