Sphärische Trigonometrie.
Stereometrie Bd. 2, Abth. 2, GDML_Books, (1877), p. 138 / Harvested from
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@article{PPN592283860+DMDLOG_0006,
     title = {Sph\"arische Trigonometrie.},
     booktitle = {Stereometrie Bd. 2, Abth. 2},
     series = {GDML\_Books},
     publisher = {Hahn},
     year = {1877},
     pages = {138},
     url = {http://dml.mathdoc.fr/item/PPN592283860+DMDLOG_0006}
}

 (éd.). Sphärische Trigonometrie., dans Stereometrie Bd. 2, Abth. 2, GDML_Books,  (1877), p. 138. http://gdmltest.u-ga.fr/item/PPN592283860+DMDLOG_0006/