GAUSS an SCHUMACHER, 12. Sept. 1850 - Fragen der Symmetrie.
Varia. Atlas des Erdmagnetismus Bd. 12, GDML_Books, (1929), p. 20 / Harvested from
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@article{PPN236060120+dmdlog21,
     title = {GAUSS an SCHUMACHER, 12. Sept. 1850  -  Fragen der Symmetrie.},
     booktitle = {Varia. Atlas des Erdmagnetismus Bd. 12},
     series = {GDML\_Books},
     year = {1929},
     pages = {20},
     url = {http://dml.mathdoc.fr/item/PPN236060120+dmdlog21}
}

 (éd.). GAUSS an SCHUMACHER, 12. Sept. 1850  -  Fragen der Symmetrie., dans Varia. Atlas des Erdmagnetismus Bd. 12, GDML_Books,  (1929), p. 20. http://gdmltest.u-ga.fr/item/PPN236060120+dmdlog21/