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@article{DAN_1979_248_4_a2, author = {M. Otelbaev}, title = {Estimates for the approximation numbers of operators connected with elliptic equations}, journal = {Doklady Akademii Nauk}, pages = {783--787}, publisher = {mathdoc}, volume = {248}, number = {4}, year = {1979}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1979_248_4_a2/} }
M. Otelbaev. Estimates for the approximation numbers of operators connected with elliptic equations. Doklady Akademii Nauk, Tome 248 (1979) no. 4, pp. 783-787. http://geodesic.mathdoc.fr/item/DAN_1979_248_4_a2/