“…Lie theory is one of the most important and powerful methods used to study differential equations. It has numerous applications in mathematics and physics, among them, to obtain exact solutions, directly or by obtaining similarity variables and similarity solutions (Gandarias and Bruzón, 2012;Gandarias and Khalique, 2016;Pocheketa, Popovych and Vaneeva, 2014); to classify invariant equations; to reduce the number of independent variables or to determine conservation laws (de la Rosa, Gandarias, and Bruzón, 2015;Ibragimov et al, 2015). The problem lies in the fact that the analysis of Lie symmetries of nonlinear equations involving arbitrary functions seems rather difficult.…”