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@article{IVM_1980_1_a6, author = {G. N. Makeev}, title = {On the question of the involutivity of systems of {Pfaffian} equations}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {39--44}, publisher = {mathdoc}, number = {1}, year = {1980}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1980_1_a6/} }
G. N. Makeev. On the question of the involutivity of systems of Pfaffian equations. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 1 (1980), pp. 39-44. http://geodesic.mathdoc.fr/item/IVM_1980_1_a6/