Existence of solutions to nonlinear Neumann boundary value problems with generalized pp-Laplacian operator

Using perturbation results on the sums of ranges of nonlinear accretive mappings of Calvert and Gupta [B.D. Calvert, C.P. Gupta, Nonlinear elliptic boundary value problems in LpLp-spaces and sums of ranges of accretive operators, Nonlinear Anal. 2 (1978) 1–26], we present some abstract existence results for the solutions of nonlinear Neumann boundary value problems involving the generalized pp-Laplacian operator. The equation discussed in this paper and the method used extend and complement some of the previous work.