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@article{DAN_1960_132_5_a13, author = {V. \`E. Lyantse}, title = {Conditions for closedness of the contraction of a self-adjoint operator}, journal = {Doklady Akademii Nauk}, pages = {1023--1026}, publisher = {mathdoc}, volume = {132}, number = {5}, year = {1960}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1960_132_5_a13/} }
V. È. Lyantse. Conditions for closedness of the contraction of a self-adjoint operator. Doklady Akademii Nauk, Tome 132 (1960) no. 5, pp. 1023-1026. http://geodesic.mathdoc.fr/item/DAN_1960_132_5_a13/