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@article{MZM_1970_7_4_a8, author = {H. Langer}, title = {On the maximal dual pairs of invariant subspaces of $J$-self-adjoint operators}, journal = {Matemati\v{c}eskie zametki}, pages = {443--447}, publisher = {mathdoc}, volume = {7}, number = {4}, year = {1970}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_1970_7_4_a8/} }
H. Langer. On the maximal dual pairs of invariant subspaces of $J$-self-adjoint operators. Matematičeskie zametki, Tome 7 (1970) no. 4, pp. 443-447. http://geodesic.mathdoc.fr/item/MZM_1970_7_4_a8/