4. GAUSS an SCHUMACHER, 1840 Juni 20
Nachtraege zur reinen Mathematik Bd. 10 Abt 1, GDML_Books, (1917), p. 108 / Harvested from
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@article{PPN236018647+dmdlog66,
     title = {4. GAUSS an SCHUMACHER, 1840 Juni 20},
     booktitle = {Nachtraege zur reinen Mathematik Bd. 10 Abt 1},
     series = {GDML\_Books},
     year = {1917},
     pages = {108},
     url = {http://dml.mathdoc.fr/item/PPN236018647+dmdlog66}
}

 (éd.). 4. GAUSS an SCHUMACHER, 1840 Juni 20, dans Nachtraege zur reinen Mathematik Bd. 10 Abt 1, GDML_Books,  (1917), p. 108. http://gdmltest.u-ga.fr/item/PPN236018647+dmdlog66/