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@article{MZM_1979_26_5_a5, author = {T. V. Andreeva}, title = {Orthogonality of elements to~a sum of subspaces}, journal = {Matemati\v{c}eskie zametki}, pages = {699--711}, publisher = {mathdoc}, volume = {26}, number = {5}, year = {1979}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_1979_26_5_a5/} }
T. V. Andreeva. Orthogonality of elements to~a sum of subspaces. Matematičeskie zametki, Tome 26 (1979) no. 5, pp. 699-711. http://geodesic.mathdoc.fr/item/MZM_1979_26_5_a5/