@article{ARM_1969__5_3_a1,
     author = {Guggenheimer, H.},
     title = {Notes on geometry},
     journal = {Archivum mathematicum},
     pages = {125--130},
     publisher = {mathdoc},
     volume = {05},
     number = {3},
     year = {1969},
     mrnumber = {0290247},
     zbl = {0235.53001},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/ARM_1969__5_3_a1/}
}