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@article{DE_1977_13_5_a3, author = {\`E. I. Grudo}, title = {Characteristic vectors of the solutions of linear homogeneous {Pfaffian} systems}, journal = {Differencialʹnye uravneni\^a}, pages = {826--840}, publisher = {mathdoc}, volume = {13}, number = {5}, year = {1977}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1977_13_5_a3/} }
È. I. Grudo. Characteristic vectors of the solutions of linear homogeneous Pfaffian systems. Differencialʹnye uravneniâ, Tome 13 (1977) no. 5, pp. 826-840. http://geodesic.mathdoc.fr/item/DE_1977_13_5_a3/