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@article{DE_1984_20_2_a1, author = {E. A. Barabanov}, title = {The highest $\sigma $-exponent of linear differential equations}, journal = {Differencialʹnye uravneni\^a}, pages = {197--207}, publisher = {mathdoc}, volume = {20}, number = {2}, year = {1984}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1984_20_2_a1/} }
E. A. Barabanov. The highest $\sigma $-exponent of linear differential equations. Differencialʹnye uravneniâ, Tome 20 (1984) no. 2, pp. 197-207. http://geodesic.mathdoc.fr/item/DE_1984_20_2_a1/