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@article{DE_1969_5_9_a15, author = {G. M. Kesel'man}, title = {A second order nonselfadjoint differential operator on the half axis}, journal = {Differencialʹnye uravneni\^a}, pages = {1700--1714}, publisher = {mathdoc}, volume = {5}, number = {9}, year = {1969}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1969_5_9_a15/} }
G. M. Kesel'man. A second order nonselfadjoint differential operator on the half axis. Differencialʹnye uravneniâ, Tome 5 (1969) no. 9, pp. 1700-1714. http://geodesic.mathdoc.fr/item/DE_1969_5_9_a15/