Janet, Maurice Sur le problème de Pfaff. (French) Zbl 0024.20103 J. Math. Pures Appl., IX. Sér. 19, 307-318 (1940). PDFBibTeX XMLCite \textit{M. Janet}, J. Math. Pures Appl. (9) 19, 307--318 (1940; Zbl 0024.20103)
Janet, M. Sur le problème de Pfaff. (French) JFM 66.0430.02 J. Math. pur. appl., Paris, (9) 19, 307-318 (1940). Reviewer: Pinl, M., Dr. (Braunschweig) PDFBibTeX XMLCite \textit{M. Janet}, J. Math. Pures Appl. (9) 19, 307--318 (1940; JFM 66.0430.02)