  Lyapunov functions are used to prove stability of equilibria, or to indicate
a gradient-like structure of a dynamical system. Zelenyak (1968) and Matano
(1988) constructed a Lyapunov function for quasilinear parabolic equations. We
modify Matano's method to construct a Lyapunov function for fully nonlinear
parabolic equations under Dirichlet and mixed nonlinear boundary conditions of
Robin type.
