Liber VI. De Focis, seu Umbilicis Sectionum Conicarum.
Elementa sectionum conicarum Tom. 2, GDML_Books, (1734), p. 78 / Harvested from
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@article{PPN591497719+DMDLOG_0003,
     title = {Liber VI. De Focis, seu Umbilicis Sectionum Conicarum.},
     booktitle = {Elementa sectionum conicarum Tom. 2},
     series = {GDML\_Books},
     publisher = {Mosca},
     address = {Neapoli},
     year = {1734},
     pages = {78},
     url = {http://dml.mathdoc.fr/item/PPN591497719+DMDLOG_0003}
}

 (éd.). Liber VI. De Focis, seu Umbilicis Sectionum Conicarum., dans Elementa sectionum conicarum Tom. 2, GDML_Books,  (1734), p. 78. http://gdmltest.u-ga.fr/item/PPN591497719+DMDLOG_0003/