SCHUMACHER an C. A. F. PETERS, 6. Juni 1850 - Desgl.
Varia. Atlas des Erdmagnetismus Bd. 12, GDML_Books, (1929), p. 304 / Harvested from
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@article{PPN236060120+dmdlog197,
     title = {SCHUMACHER an C. A. F. PETERS, 6. Juni 1850 -  Desgl.},
     booktitle = {Varia. Atlas des Erdmagnetismus Bd. 12},
     series = {GDML\_Books},
     year = {1929},
     pages = {304},
     url = {http://dml.mathdoc.fr/item/PPN236060120+dmdlog197}
}

 (éd.). SCHUMACHER an C. A. F. PETERS, 6. Juni 1850 -  Desgl., dans Varia. Atlas des Erdmagnetismus Bd. 12, GDML_Books,  (1929), p. 304. http://gdmltest.u-ga.fr/item/PPN236060120+dmdlog197/