General Solution of a Fractional Diffusion-Advection Equation for Solar   Cosmic-Ray Transport
  In this effort we exactly solve the fractional diffusion-advection equation for solar cosmic-ray transport proposed in \cite{LE2014} and give its {\it general solution} in terms of hypergeometric distributions. Also, we regain all the results and approximations given in \cite{LE2014} as {\it particular cases} of our general solution. 
M. C. Rocca, A. R. Plastino, A. Plastino, A. L. De Paoli
astro-ph.HE cond-mat.stat-mech hep-th math-ph math.MP