  The Dirichlet product of functions on a semi-Riemann domain and generalized
Euler vector fields, which include the radial, $\bar \partial$-Euler, and the
$\bar \partial$-Neumann vector fields, are introduced. The integral means and
the harmonic residues of functions on a Riemann domain are studied. The notion
of semi-harmonicity of functions on a complex space is introduced. It is shown
that, on a Riemann domain, the semi-harmonicity of a locally forwardly
$L^2$-function is characterized by local mean-value properties as well as by
weak-harmonicity. In particular, the Weyl's Lemma is extended to a Riemann
domain.
