GAUSS an SPEHR, 4. April 1829
Varia. Atlas des Erdmagnetismus Bd. 12, GDML_Books, (1929), p. 99 / Harvested from
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@article{PPN236060120+dmdlog68,
     title = {GAUSS an SPEHR, 4. April 1829},
     booktitle = {Varia. Atlas des Erdmagnetismus Bd. 12},
     series = {GDML\_Books},
     year = {1929},
     pages = {99},
     url = {http://dml.mathdoc.fr/item/PPN236060120+dmdlog68}
}

 (éd.). GAUSS an SPEHR, 4. April 1829, dans Varia. Atlas des Erdmagnetismus Bd. 12, GDML_Books,  (1929), p. 99. http://gdmltest.u-ga.fr/item/PPN236060120+dmdlog68/