Global characterization of variational first-order quasi-linear equations
Keywords: affine Lagrangian; Euler-Lagrange equations; first-order quasi-linear equations; jet bundles; Poincaré-Cartan form; Primary 58E30; Secondary 35F05, 37K05, 58A20; 02.30.Jr; 02.30.Xx; 02.40.Ma; 02.40.Vh; 11.10.Ef; 11.10.Kk;