2. Die Berührungstransformationen.
Geometrie Bd. 2, GDML_Books, (1968), p. 119 / Harvested from
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@article{PPN37649882X+dmdlog70,
     title = {2. Die Ber\"uhrungstransformationen.},
     booktitle = {Geometrie Bd. 2},
     series = {GDML\_Books},
     year = {1968},
     pages = {119},
     url = {http://dml.mathdoc.fr/item/PPN37649882X+dmdlog70}
}

 (éd.). 2. Die Berührungstransformationen., dans Geometrie Bd. 2, GDML_Books,  (1968), p. 119. http://gdmltest.u-ga.fr/item/PPN37649882X+dmdlog70/