The Characterization of Radial Subspaces of Besov- and Lizorkin-Triebel Spaces by Differences

Winfried Sickel, Leszek Skrzypczak, Jan Vybiral

We continue our earlier investigations of radial subspaces of Besov and Lizorkin-Triebel spaces on ${\mathbb{R}}^d$. This time we study characterizations of these subspaces by differences.