Radius of comparison and mean topological dimension: Zd-actions

Consider aminimal-free topological dynamical system( X, Z(d)). It is shown that the radius of comparison of the crossed product C*-algebra C(X) (sic) Z(d) is at most half the mean topological dimension of ( X, Z(d)). As a consequence, the C*-algebra C(X) (sic) Z(d) is classified by the Elliott invariant if the mean dimension of (X, Z(d)) is zero.