Paper XXXII - XXXIII. On the Conditions of Perpendicularity in a Parallelepipedal System.
The collected mathematical papers of Henry John Stephen Smith Vol. 2, GDML_Books, (1894), p. 191 / Harvested from
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@article{PPN588764248+DMDLOG_0012,
     title = {Paper XXXII - XXXIII. On the Conditions of Perpendicularity in a Parallelepipedal System.},
     booktitle = {The collected mathematical papers of Henry John Stephen Smith Vol. 2},
     series = {GDML\_Books},
     publisher = {Clarendon Press},
     address = {Oxford},
     year = {1894},
     pages = {191},
     url = {http://dml.mathdoc.fr/item/PPN588764248+DMDLOG_0012}
}

 (éd.). Paper XXXII - XXXIII. On the Conditions of Perpendicularity in a Parallelepipedal System., dans The collected mathematical papers of Henry John Stephen Smith Vol. 2, GDML_Books,  (1894), p. 191. http://gdmltest.u-ga.fr/item/PPN588764248+DMDLOG_0012/