§ 2. Doppelverhältnisse
Lehrbuch der Algebra Bd. 3, GDML_Books, (1908), p. 5 / Harvested from
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@article{PPN234736674+dmdlog11,
     title = {\S\ 2. Doppelverh\"altnisse},
     booktitle = {Lehrbuch der Algebra Bd. 3},
     series = {GDML\_Books},
     year = {1908},
     pages = {5},
     url = {http://dml.mathdoc.fr/item/PPN234736674+dmdlog11}
}

 (éd.). § 2. Doppelverhältnisse, dans Lehrbuch der Algebra Bd. 3, GDML_Books,  (1908), p. 5. http://gdmltest.u-ga.fr/item/PPN234736674+dmdlog11/