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@article{DAN_1970_192_4_a0, author = {E. S. Birger}, title = {The nonselfadjoint operator $-y''+p(x)y$ on the axis $(-\infty,\infty)$}, journal = {Doklady Akademii Nauk}, pages = {711--713}, publisher = {mathdoc}, volume = {192}, number = {4}, year = {1970}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1970_192_4_a0/} }
E. S. Birger. The nonselfadjoint operator $-y''+p(x)y$ on the axis $(-\infty,\infty)$. Doklady Akademii Nauk, Tome 192 (1970) no. 4, pp. 711-713. http://geodesic.mathdoc.fr/item/DAN_1970_192_4_a0/