Cap. VIII. Die trigonometrischen Functionen.
Planimetrie und ebene Trigonometrie Theil 1, GDML_Books, (1874), p. 163 / Harvested from
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@article{PPN587689242+DMDLOG_0015,
     title = {Cap. VIII. Die trigonometrischen Functionen.},
     booktitle = {Planimetrie und ebene Trigonometrie Theil 1},
     series = {GDML\_Books},
     publisher = {Teubner},
     address = {Leipzig},
     year = {1874},
     pages = {163},
     url = {http://dml.mathdoc.fr/item/PPN587689242+DMDLOG_0015}
}

 (éd.). Cap. VIII. Die trigonometrischen Functionen., dans Planimetrie und ebene Trigonometrie Theil 1, GDML_Books,  (1874), p. 163. http://gdmltest.u-ga.fr/item/PPN587689242+DMDLOG_0015/