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@article{DAN_1966_169_1_a1, author = {G. K. Langer}, title = {Invariant subspaces of linear operators acting in a space with indefinite metric}, journal = {Doklady Akademii Nauk}, pages = {12--15}, publisher = {mathdoc}, volume = {169}, number = {1}, year = {1966}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1966_169_1_a1/} }
G. K. Langer. Invariant subspaces of linear operators acting in a space with indefinite metric. Doklady Akademii Nauk, Tome 169 (1966) no. 1, pp. 12-15. http://geodesic.mathdoc.fr/item/DAN_1966_169_1_a1/