Generalized Bessel potentials on Lipschitz type spaces

We introduce generalizations of Bessel potentials by considering operators of the form φ[(I – Δ)^–½] where the functions φ extend the classical power case. The kernel of such an operator is subordinate to a growth function η. We explore conditions on η in such a way that these operators become isomorphisms between generalized Lipschitz spaces. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)