“…Exact solutions of a nonlinear evolution equation offer direct and valuable insight into the physical aspects of the problem modeled by the equation. Therefore, the search for exact solutions of nonlinear evolution equations has gained much attention in the past decades from the mathematical physics community, and a large number of methods have been proposed, such as the tanh method [1,2], the inverse scattering method [3], the homogeneous balance method [4], the (G /G)-expansion method [5,6], the sine-cosine method [7], the Frobenius integrable decomposition method [8], the improved Exp-function method [9], the generalized Kudryashov method [10], the local fractional Riccati differential equation method [11], the Hirota bilinear method [12][13][14], the Darboux transformation method [15,16] and the group methods [17][18][19][20][21][22][23][24][25]. As stated in [26], symmetry is the key to solving differential equations.…”