Global strong solvability of Dirichlet problem for a class of nonlinear elliptic equations in the plane

Global solvability and uniqueness results are established for Dirichlet's problem for a class of nonlinear differential equations on a convex domain in the plane, where the nonlinear operator is elliptic in sense of Campanato. We prove existence by means of the Leray-Schauder fixed point theorem, using Alexandrov-Pucci maximum principle in order to find a priori estimate for the solution.