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@article{DE_1979_15_4_a1, author = {\`E. I. Grudo}, title = {Analogues of the fundamental theorems of the first method of {Ljapunov} for {Pfaffian} systems}, journal = {Differencialʹnye uravneni\^a}, pages = {589--599}, publisher = {mathdoc}, volume = {15}, number = {4}, year = {1979}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1979_15_4_a1/} }
È. I. Grudo. Analogues of the fundamental theorems of the first method of Ljapunov for Pfaffian systems. Differencialʹnye uravneniâ, Tome 15 (1979) no. 4, pp. 589-599. http://geodesic.mathdoc.fr/item/DE_1979_15_4_a1/