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@article{DE_1966_2_4_a4, author = {M. V. Fedoryuk}, title = {The asymptotics of solutions to ordinary linear differential equations of the $n$-th order}, journal = {Differencialʹnye uravneni\^a}, pages = {492--507}, publisher = {mathdoc}, volume = {2}, number = {4}, year = {1966}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1966_2_4_a4/} }
M. V. Fedoryuk. The asymptotics of solutions to ordinary linear differential equations of the $n$-th order. Differencialʹnye uravneniâ, Tome 2 (1966) no. 4, pp. 492-507. http://geodesic.mathdoc.fr/item/DE_1966_2_4_a4/