Three critical points for perturbed nonsmooth functionals and applications

A recently established three-critical-points theorem of Ricceri relating to continuously Gâteaux differentiable functionals, based on a minimax inequality and on a truncation argument, is extended to Motreanu–Panagiotopoulos functionals. As an application, multiplicity results, also yielding a uniform bound on the norms of solutions, are obtained for variational–hemivariational inequalities depending on two parameters.