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@article{DAN_1976_231_5_a1, author = {Yu. Ya. Belov}, title = {On some systems of linear differential equations with a small parameter}, journal = {Doklady Akademii Nauk}, pages = {1037--1040}, publisher = {mathdoc}, volume = {231}, number = {5}, year = {1976}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1976_231_5_a1/} }
Yu. Ya. Belov. On some systems of linear differential equations with a small parameter. Doklady Akademii Nauk, Tome 231 (1976) no. 5, pp. 1037-1040. http://geodesic.mathdoc.fr/item/DAN_1976_231_5_a1/