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@article{DE_1976_12_9_a5, author = {N. P. Morozov}, title = {A transformation of an asymptotic expansion of the period}, journal = {Differencialʹnye uravneni\^a}, pages = {1580--1586}, publisher = {mathdoc}, volume = {12}, number = {9}, year = {1976}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1976_12_9_a5/} }
N. P. Morozov. A transformation of an asymptotic expansion of the period. Differencialʹnye uravneniâ, Tome 12 (1976) no. 9, pp. 1580-1586. http://geodesic.mathdoc.fr/item/DE_1976_12_9_a5/