GAUSS an SCHUMACHER, 26. Sept. 1844 - Beweis der Gleichung (....a)2 = 1 + 8 +... + (a Â? 1 )3 + a3.
Varia. Atlas des Erdmagnetismus Bd. 12, GDML_Books, (1929), p. 11 / Harvested from
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@article{PPN236060120+dmdlog11,
     title = {GAUSS an SCHUMACHER, 26. Sept. 1844  -  Beweis der Gleichung (....a)2 = 1 + 8 +...  + (a \^A? 1 )3  + a3.},
     booktitle = {Varia. Atlas des Erdmagnetismus Bd. 12},
     series = {GDML\_Books},
     year = {1929},
     pages = {11},
     url = {http://dml.mathdoc.fr/item/PPN236060120+dmdlog11}
}

 (éd.). GAUSS an SCHUMACHER, 26. Sept. 1844  -  Beweis der Gleichung (....a)2 = 1 + 8 +...  + (a Â? 1 )3  + a3., dans Varia. Atlas des Erdmagnetismus Bd. 12, GDML_Books,  (1929), p. 11. http://gdmltest.u-ga.fr/item/PPN236060120+dmdlog11/