SCHUMACHER an GAUSS, 5, April 1842
Varia. Atlas des Erdmagnetismus Bd. 12, GDML_Books, (1929), p. 15 / Harvested from
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@article{PPN236060120+dmdlog16,
     title = {SCHUMACHER an GAUSS, 5, April 1842},
     booktitle = {Varia. Atlas des Erdmagnetismus Bd. 12},
     series = {GDML\_Books},
     year = {1929},
     pages = {15},
     url = {http://dml.mathdoc.fr/item/PPN236060120+dmdlog16}
}

 (éd.). SCHUMACHER an GAUSS, 5, April 1842, dans Varia. Atlas des Erdmagnetismus Bd. 12, GDML_Books,  (1929), p. 15. http://gdmltest.u-ga.fr/item/PPN236060120+dmdlog16/