Paper XX. Observatio Geometrica.
The collected mathematical papers of Henry John Stephen Smith Vol. 1, GDML_Books, (1894), p. 541 / Harvested from
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@article{PPN588764140+DMDLOG_0020,
     title = {Paper XX. Observatio Geometrica.},
     booktitle = {The collected mathematical papers of Henry John Stephen Smith Vol. 1},
     series = {GDML\_Books},
     publisher = {Clarendon Press},
     address = {Oxford},
     year = {1894},
     pages = {541},
     url = {http://dml.mathdoc.fr/item/PPN588764140+DMDLOG_0020}
}

 (éd.). Paper XX. Observatio Geometrica., dans The collected mathematical papers of Henry John Stephen Smith Vol. 1, GDML_Books,  (1894), p. 541. http://gdmltest.u-ga.fr/item/PPN588764140+DMDLOG_0020/