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@article{DE_1989_25_10_a31, author = {N. A. Chernyavskaya and L. A. Shuster}, title = {The {WKB} method}, journal = {Differencialʹnye uravneni\^a}, pages = {1826--1829}, publisher = {mathdoc}, volume = {25}, number = {10}, year = {1989}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1989_25_10_a31/} }
N. A. Chernyavskaya; L. A. Shuster. The WKB method. Differencialʹnye uravneniâ, Tome 25 (1989) no. 10, pp. 1826-1829. http://geodesic.mathdoc.fr/item/DE_1989_25_10_a31/