A direct theorem on approximation ``by angle'' in the spaces \(L_ p\), \(0<p<1\)
A direct theorem on the approximation ``by angle'' (\textit{M. K. Potapov} [Math. Balkanica 2, 183-198 (1972; Zbl 0293.41018)]) in \(L_{p^*}\), \(0 < p < 1\), in the two-variables case is proved through the mixed modulus of smoothness in \(L_{p^*}\).
scientific article; zbMATH DE number 578695