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@article{DE_1980_16_9_a18, author = {I. N. Sergeev}, title = {Invariance of central exponents with respect to perturbations which approach zero at infinity}, journal = {Differencialʹnye uravneni\^a}, pages = {1719}, publisher = {mathdoc}, volume = {16}, number = {9}, year = {1980}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1980_16_9_a18/} }
I. N. Sergeev. Invariance of central exponents with respect to perturbations which approach zero at infinity. Differencialʹnye uravneniâ, Tome 16 (1980) no. 9. http://geodesic.mathdoc.fr/item/DE_1980_16_9_a18/