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@article{TM_1992_198_a13, author = {V. T. Shevaldin}, title = {Lower estimations of widths some classes of periodic functions}, journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova}, pages = {242--267}, publisher = {mathdoc}, volume = {198}, year = {1992}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/TM_1992_198_a13/} }
V. T. Shevaldin. Lower estimations of widths some classes of periodic functions. Trudy Matematicheskogo Instituta imeni V.A. Steklova, Proceedings of the All-Union school on the theory of functions, Tome 198 (1992), pp. 242-267. http://geodesic.mathdoc.fr/item/TM_1992_198_a13/