A Phragmèn–Lindelöf theorem and the behavior at infinity of solutions of non-hyperbolic equations

Abstract

We prove a Phragmn-Lindelf theorem which yields the behavior at infinity of bounded solutions of Dirichlet problems for non-hyperbolic (e.g., elliptic, parabolic) quasilinear second-order partial differential equations in terms of particular solutions of appropriate ordinary differential equations.