“…Many mathematical methods, such as dual approach [3,22,[24][25][26], iterative techniques [19,[27][28][29][30], fixed point theorem [5,14,21], variational methods [6,15,23] and normal boundary intersection method [9,10], have been employed to solve the properties and control problems for various differential equations. In particular, by using a constrained minimization argument Poppenberg et al [15] established the existence of positive ground state solution for quasilinear Schrödinger equation (4).…”