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@article{DAN_1965_165_6_a3, author = {Allan M. Krall}, title = {On non-self-adjoint ordinary differential operators of the second order}, journal = {Doklady Akademii Nauk}, pages = {1235--1237}, publisher = {mathdoc}, volume = {165}, number = {6}, year = {1965}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1965_165_6_a3/} }
Allan M. Krall. On non-self-adjoint ordinary differential operators of the second order. Doklady Akademii Nauk, Tome 165 (1965) no. 6, pp. 1235-1237. http://geodesic.mathdoc.fr/item/DAN_1965_165_6_a3/