@article{PPN585262896+DMDLOG_0021, title = {Chapter XVII. Equations of the Second Degree.}, booktitle = {Algebra Part 1}, series = {GDML\_Books}, publisher = {Black}, address = {Edinburgh}, year = {1889}, pages = {396}, url = {http://dml.mathdoc.fr/item/PPN585262896+DMDLOG_0021} }
(éd.). Chapter XVII. Equations of the Second Degree., dans Algebra Part 1, GDML_Books, (1889), p. 396. http://gdmltest.u-ga.fr/item/PPN585262896+DMDLOG_0021/