Kolmogorov and trigonometric widths of the Besov classes $B^r_{p,\theta}$ of multivariate periodic functions

Precise (in order) estimates of the Kolmogorov widths in the space $L_q$, $1<q<\infty$, of the classes $B^r_{1,\theta}$ and $B^r_{\infty,\theta}$ and also of the trigonometric widths of the classes $B^r_{p,\theta}$ in $L_q$ for $p$ and $q$ satisfying certain relations are obtained.
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