@article{MZ_1957__67_169685,
     author = {Helmut Salzmann},
     title = {Topologische projektive {Ebenen.}},
     journal = {Mathematische Zeitschrift},
     pages = {436--466},
     year = {1957},
     volume = {67},
     language = {de},
     url = {http://geodesic.mathdoc.fr/item/MZ_1957__67_169685/}
}