Excerpt from Le ons sur le Probl me de Pfaff Enfin, dans les trois derniers Chapitres, j'expose quelques uns des progr s les plus r cents acquis la Science, relatifs aux syst mes de Pfaff. Les plus importants de ces progr s sont dus M. Cartan, dont on trouvera le nom presque chaque page de ces trois Chapitres. Je souhaite que cet expos rapide puisse engager les jeunes math maticiens tudier plus fond ces l gantes m thodes, dont l'auteur a d j fait de si belles applications. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.