@article{ELMA_1964__19_140791,
     author = {J. Mall},
     title = {Herleitung der hyperbolischen {Trigonometrie} aus dem allgemeinen {Poincar\'emodell.}},
     journal = {Elemente der Mathematik},
     pages = {77--81},
     publisher = {mathdoc},
     volume = {19},
     year = {1964},
     zbl = {0122.38103},
     url = {http://geodesic.mathdoc.fr/item/ELMA_1964__19_140791/}
}