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@article{IVM_1971_7_a15, author = {L. D. \`Eskin}, title = {The asymptotic behavior of the solutions of the system $Y''-Q(x)Y'-P(x)Y=0${.~I}}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {122--136}, publisher = {mathdoc}, number = {7}, year = {1971}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1971_7_a15/} }
L. D. Èskin. The asymptotic behavior of the solutions of the system $Y''-Q(x)Y'-P(x)Y=0$.~I. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 7 (1971), pp. 122-136. http://geodesic.mathdoc.fr/item/IVM_1971_7_a15/