@article{GDZPPN002270846, title = {Zur Theorie der unendlichen Differentialsysteme}, journal = {Mathematische Annalen}, volume = {95}, year = {1926}, pages = {544-556}, zbl = {52.0403.02}, url = {http://dml.mathdoc.fr/item/GDZPPN002270846} }
Wintner, A. Zur Theorie der unendlichen Differentialsysteme. Mathematische Annalen, Tome 95 (1926) pp. 544-556. http://gdmltest.u-ga.fr/item/GDZPPN002270846/