Chapter IV. On ratios and proportions.
Arithmetical Algebra Vol. 1, GDML_Books, (1842), p. 154 / Harvested from
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@article{PPN585270759+DMDLOG_0008,
     title = {Chapter IV. On ratios and proportions.},
     booktitle = {Arithmetical Algebra Vol. 1},
     series = {GDML\_Books},
     publisher = {Deighton [u.a.]},
     address = {Cambridge},
     year = {1842},
     pages = {154},
     url = {http://dml.mathdoc.fr/item/PPN585270759+DMDLOG_0008}
}

 (éd.). Chapter IV. On ratios and proportions., dans Arithmetical Algebra Vol. 1, GDML_Books,  (1842), p. 154. http://gdmltest.u-ga.fr/item/PPN585270759+DMDLOG_0008/