Existence of multiple positive solutions for a p–qp–q-Laplacian system with critical nonlinearities

In this paper, our main purpose is to establish the existence of multiple positive solutions of a p–qp–q-Laplacian system with convex and Sobolev critical nonlinearities by some standard variational methods, whose key is to construct homotopies between ΩΩ and levels of the functional JλθJλθ, and some analytical techniques.