  This paper is a continuation of our earlier paper in which we have derived
the solution of an unified fractional reaction-diffusion equation associated
with the Caputo derivative as the time-derivative and the Riesz-Feller
fractional derivative as the space-derivative. In this paper, we consider an
unified reaction-diffusion equation with Riemann-Liouville fractional
derivative as the time-derivative and Riesz-Feller derivative as the
space-derivative. The solution is derived by the application of the Laplace and
Fourier transforms in a compact and closed form in terms of the H-function. The
results derived are of general character and include the results investigated
earlier by Kilbas et al. (2006a), Saxena et al. (2006c), and Mathai et al.
(2010). The main result is given in the form of a theorem. A number of
interesting special cases of the theorem are also given as corollaries.
