“…The variational principle is also the theoretical basis for the variational iteration method, where the general Lagrange multiplier is identified by solving the Euler–Lagrange equations of the correction functional (Anjum and He, 2019; He et al , 2014; Inc et al , 2018; Jafari et al , 2018; Baleanu et al , 2018; Dogan Durgun and Konuralp, 2018). Recently the variational principle was successfully applied to solitary theory (Biswas et al , 2017; El-Kalaawy, 2016; El-Kalaawy, 2017), and it might be also a potential tool for shock identification in a transonic flow.…”