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@article{DE_1984_20_12_a3, author = {G. S. Krechetov}, title = {Lyapunov functions for second-order autonomous systems of classes $5$--$7$}, journal = {Differencialʹnye uravneni\^a}, pages = {2048--2053}, publisher = {mathdoc}, volume = {20}, number = {12}, year = {1984}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1984_20_12_a3/} }
G. S. Krechetov. Lyapunov functions for second-order autonomous systems of classes $5$--$7$. Differencialʹnye uravneniâ, Tome 20 (1984) no. 12, pp. 2048-2053. http://geodesic.mathdoc.fr/item/DE_1984_20_12_a3/