Lipschitz spaces and Calderon-Zygmund operators associated to   non-doubling measures
  In the setting of $\R^d$ with an $n-$dimensional measure $\mu,$ we give several characterizations of Lipschitz spaces in terms of mean oscillations involving $\mu.$ We also show that Lipschitz spaces are preserved by those Calderon-Zygmund operators $T$ associated to the measure $\mu$ for which T(1) is the Lipschitz class $0.$ 
Jose Garcia-Cuerva and A. Eduardo Gatto