XV. Kapitel. Freie Perspektive.
Lehrbuch der darstellenden Geometrie Bd. 2, GDML_Books, (1896), p. 411 / Harvested from
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@article{PPN592034941+DMDLOG_0011,
     title = {XV. Kapitel. Freie Perspektive.},
     booktitle = {Lehrbuch der darstellenden Geometrie Bd. 2},
     series = {GDML\_Books},
     publisher = {Veit},
     year = {1896},
     pages = {411},
     url = {http://dml.mathdoc.fr/item/PPN592034941+DMDLOG_0011}
}

 (éd.). XV. Kapitel. Freie Perspektive., dans Lehrbuch der darstellenden Geometrie Bd. 2, GDML_Books,  (1896), p. 411. http://gdmltest.u-ga.fr/item/PPN592034941+DMDLOG_0011/