@misc{Bourdon_Pierre-Louis-Marie_(1779–1854)_Éléments_1867, author={Bourdon, Pierre-Louis-Marie (1779–1854)}, copyright={Public Domain}, address={Paris}, howpublished={online}, year={1867}, publisher={Gauthier-Villars}, language={fre}, title={Éléments d'arithmétique}, type={Text}, URL={http://rcin.org.pl/Content/17675/PDF/WA35_6403_6276_Elements.pdf}, }