Voir la notice de l'article provenant de la source Math-Net.Ru
@article{IVM_1959_2_a2, author = {Yu. E. Borovskii}, title = {Completely integrable {Pfaffian} systems}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {28--40}, publisher = {mathdoc}, number = {2}, year = {1959}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1959_2_a2/} }
Yu. E. Borovskii. Completely integrable Pfaffian systems. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 2 (1959), pp. 28-40. http://geodesic.mathdoc.fr/item/IVM_1959_2_a2/