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@article{MZM_2007_82_3_a4, author = {E. D. Livshits}, title = {On $n${-Term} {Approximation} with {Positive} {Coefficients}}, journal = {Matemati\v{c}eskie zametki}, pages = {373--382}, publisher = {mathdoc}, volume = {82}, number = {3}, year = {2007}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_2007_82_3_a4/} }
E. D. Livshits. On $n$-Term Approximation with Positive Coefficients. Matematičeskie zametki, Tome 82 (2007) no. 3, pp. 373-382. http://geodesic.mathdoc.fr/item/MZM_2007_82_3_a4/