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@article{DE_1993_29_1_a4, author = {V. D. Budaev}, title = {Some properties of root vector functions of a higher-order operator}, journal = {Differencialʹnye uravneni\^a}, pages = {30--40}, publisher = {mathdoc}, volume = {29}, number = {1}, year = {1993}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1993_29_1_a4/} }
V. D. Budaev. Some properties of root vector functions of a higher-order operator. Differencialʹnye uravneniâ, Tome 29 (1993) no. 1, pp. 30-40. http://geodesic.mathdoc.fr/item/DE_1993_29_1_a4/