  Anomalous diffusion phenomena are ubiquitous in complex media, such as
biological tissues.
  A wide class of sub-diffusive phenomena phenomena is described by the
time-fractional diffusion equation.
  The paper investigates the case of anisotropic fractional diffusion in the
Euclidean space.
  The solution of the fractional sub-diffusion equation can be expressed in
terms of the Wright function and its spatial derivatives, parametrized by the
directional unit vector (or alternatively a normal hyperplane).
  Moreover, the multidimensional case could be expressed as a transformation of
the one-dimensional case.
