Grundbegriffe der sphärischen Trigonometrie.
Arithmetik, Algebra, Analysis Bd. 1, GDML_Books, (1968), p. 189 / Harvested from
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@article{PPN376503645+dmdlog85,
     title = {Grundbegriffe der sph\"arischen Trigonometrie.},
     booktitle = {Arithmetik, Algebra, Analysis Bd. 1},
     series = {GDML\_Books},
     year = {1968},
     pages = {189},
     url = {http://dml.mathdoc.fr/item/PPN376503645+dmdlog85}
}

 (éd.). Grundbegriffe der sphärischen Trigonometrie., dans Arithmetik, Algebra, Analysis Bd. 1, GDML_Books,  (1968), p. 189. http://gdmltest.u-ga.fr/item/PPN376503645+dmdlog85/