Existence of nontrivial solutions for semilinear problems with strictly differentiable nonlinearity. Lancelotti, Sergio — 2006 Abstract and Applied Analysis
Linking over cones and nontrivial solutions for p-Laplace equations with p-superlinear nonlinearity Marco Degiovanni; Sergio Lancelotti — 2007 Annales de l'I.H.P. Analyse non linéaire