@article{MZ_1967__100_170808,
     author = {Armin Leutbecher},
     title = {\"Uber {Spitzen} deskontinuierlicher {Gruppen} von lineargebrochenen {Transformationen.}},
     journal = {Mathematische Zeitschrift},
     pages = {183--200},
     publisher = {mathdoc},
     volume = {100},
     year = {1967},
     zbl = {0157.13502},
     url = {http://geodesic.mathdoc.fr/item/MZ_1967__100_170808/}
}