Jacques Charles François Sturm
Jacques Charles François Sturm was a French mathematician, who made a significant addition to equation theory with his work, Sturm's theorem.
Jacques Charles François Sturm portrayed by Jean-Daniel Colladon
Cours de mécanique de l'École polytechnique, 1871
Joseph Liouville was a French mathematician and engineer.
Joseph Liouville
Title page of the first volume of Journal de Mathématiques Pures et Appliquées in 1836.