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@article{DE_1980_16_3_a8, author = {V. P. Skripnik}, title = {Degenerate systems and a small parameter multiplying the derivative}, journal = {Differencialʹnye uravneni\^a}, pages = {454--461}, publisher = {mathdoc}, volume = {16}, number = {3}, year = {1980}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1980_16_3_a8/} }
V. P. Skripnik. Degenerate systems and a small parameter multiplying the derivative. Differencialʹnye uravneniâ, Tome 16 (1980) no. 3, pp. 454-461. http://geodesic.mathdoc.fr/item/DE_1980_16_3_a8/