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@article{DAN_1964_159_4_a14, author = {A. I. Perov}, title = {On a higher-dimensional linear differential equation of second order}, journal = {Doklady Akademii Nauk}, pages = {755--758}, publisher = {mathdoc}, volume = {159}, number = {4}, year = {1964}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1964_159_4_a14/} }
A. I. Perov. On a higher-dimensional linear differential equation of second order. Doklady Akademii Nauk, Tome 159 (1964) no. 4, pp. 755-758. http://geodesic.mathdoc.fr/item/DAN_1964_159_4_a14/