5.) Beltrami's Teoria fondamentale.
Gehalten während des Wintersemesters 1889 - 90 Vorlesung 1, GDML_Books, (1892), p. 236 / Harvested from
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@article{PPN51697307X+dmdlog38,
     title = {5.) Beltrami's Teoria fondamentale.},
     booktitle = {Gehalten w\"ahrend des Wintersemesters 1889 - 90 Vorlesung 1},
     series = {GDML\_Books},
     year = {1892},
     pages = {236},
     url = {http://dml.mathdoc.fr/item/PPN51697307X+dmdlog38}
}

 (éd.). 5.) Beltrami's Teoria fondamentale., dans Gehalten während des Wintersemesters 1889 - 90 Vorlesung 1, GDML_Books,  (1892), p. 236. http://gdmltest.u-ga.fr/item/PPN51697307X+dmdlog38/