“…However, just like the integer-order PDEs, there exists no commonly available method to study fractional PDEs, especially for finding exact solutions as well as numerical ones. Thus, many researchers try to extend certain known effective techniques of solving integer-order PDEs to deal with fractional PDEs such as the subequation method 8,9 , homotopy perturbation method 10 , differential transform method 11 , variational iteration method, 12 invariant subspace method 13 , power series method, 14 and so on. It is worth saying that in the last several decades Lie group theory has been evolved into one of the most important tools to study PDEs as well as fractional PDEs [15][16][17][18][19][20] .…”