Widths and average widths of Sobolev classes
Let \(W^r_{\overline p}(I^d)\) be the unit ball in the isotropic Sobolev space defined over the mixed \(L_{\overline p}= L_{p_1,\dots, p_d}\) space on \(\mathbb{R}^d\) or \(d\)-dimensional torus \(T^d\). The authors generalize the well-known results of the width of a different kind over \(L_p(I^d)\), \(1\leq p\leq\infty\), to the case of \(W^r_{\overline p}(I^d)\).
scientific article; zbMATH DE number 1931035