“…Thereafter, many authors have investigated various kinds of nonlinear mixed monotone operators in Banach spaces such as nonlinear operators with concave-convex (see [4]), mixed monotone operators with α-concave-convex (see [33,34]), nonlinear operators with φ-concave-convex (see [10,26]), nonlinear operators with e-concave-convex (see [39]), and also obtained a lot of important results on mixed monotone operators (see [1,2,7,8,11,13,16,17,21,22,23,24,27,28,29,31,32,38]). These studies not only have theoretical significance but also have a wide range of applications in engineering, nuclear physics, biology, chemistry, technology, etc.…”