Fig. 1 - 3.
Die Buchstabenrechnung Theil 1, GDML_Books, (1833), p. 465 / Harvested from
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@article{PPN591917149+DMDLOG_0008,
     title = {Fig. 1 - 3.},
     booktitle = {Die Buchstabenrechnung Theil 1},
     series = {GDML\_Books},
     publisher = {Duncker u. Humblot},
     address = {Berlin},
     year = {1833},
     pages = {465},
     url = {http://dml.mathdoc.fr/item/PPN591917149+DMDLOG_0008}
}

 (éd.). Fig. 1 - 3., dans Die Buchstabenrechnung Theil 1, GDML_Books,  (1833), p. 465. http://gdmltest.u-ga.fr/item/PPN591917149+DMDLOG_0008/