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@article{IVM_1974_10_a10, author = {L. D. \`Eskin}, title = {The asymptotic behavior of the solutions of the system $Y''-Q(x)Y'-P(x)Y=0${.~IV}}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {88--103}, publisher = {mathdoc}, number = {10}, year = {1974}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1974_10_a10/} }
L. D. Èskin. The asymptotic behavior of the solutions of the system $Y''-Q(x)Y'-P(x)Y=0$.~IV. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 10 (1974), pp. 88-103. http://geodesic.mathdoc.fr/item/IVM_1974_10_a10/