I recently came across a paper by the mathematician Edouard Lucas,
"Recherches sur l’analyse indéterminée et l’arithmétique de Diophante" Moulins: Desrosiers, 1873; reprint Paris: Blanchard, 1961.
I'm looking for the above paper, either downloadable or purchasable copy.
Any help will be appreciated.
You can read this online or download as PDF: https://books.google.com/books/about/Recherches_sur_l_analyse_ind%C3%A9termin%C3%A9e.html?id=OP4pmQEACAAJ