  Let $V$ be a projective limit, with respect to the renormalized norm
mappings, of the groups of principal units corresponding to a strictly
increasing sequence of finite separable totally and tamely ramified Galois
extensions of a local field. We study the structure of the dual group $V'$,
introduce and investigate a fractional differentiation operator on $V$, and the
corresponding L\'evy process. Part I: Potential Anal., 10 (1999), 305-325.
