Verbesserungen.
Geometrie und Trigonometrie Abth. 2, GDML_Books, (1851), p. 61 / Harvested from
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@article{PPN58470691X+DMDLOG_0005,
     title = {Verbesserungen.},
     booktitle = {Geometrie und Trigonometrie Abth. 2},
     series = {GDML\_Books},
     publisher = {Lampart},
     address = {Augsburg},
     year = {1851},
     pages = {61},
     url = {http://dml.mathdoc.fr/item/PPN58470691X+DMDLOG_0005}
}

 (éd.). Verbesserungen., dans Geometrie und Trigonometrie Abth. 2, GDML_Books,  (1851), p. 61. http://gdmltest.u-ga.fr/item/PPN58470691X+DMDLOG_0005/