Address. Department of Mathematics, EPFL, 1015 Lausanne, Switzerland
E-mail: Bernard.Dacorogna@epfl.ch
Abstract. We discuss the existence of almost everywhere solutions of nonlinear PDE's of first (in the scalar and vectorial cases) and second order.
AMS classification. 35D05, 35F05.
Key words. A. e. solutions of nonlinear PDE's, Baire category theorem, quasiconvex hull.