@article{JRAM_1974__265_151406,
     author = {J\"urgen T\"olke},
     title = {Kinematik der hpyerbolischen {Ebene.} {I.}},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {145--153},
     publisher = {mathdoc},
     volume = {265},
     year = {1974},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1974__265_151406/}
}