A result on elliptic systems with Neumann conditions via Ricceri's three critical points theorem

This paper is concerned with the study of the existence of nontrivial solutions for elliptic systems involving the p-Laplacian. By using the result of [B. Ricceri, A three critical points theorem revisited, Nonlinear Anal. (2008), in press (doi:10.1016/j.na.2008.04.010)], we establish the existence of at least three solutions.