A global a posteriori error estimate for quasilinear elliptic problems

A global a posteriori error estimate, valid even if uniqueness fails, is obtained for a class of quasilinear elliptic partial differential equations. It is applied to the analysis of finite element methods for such problems, and to a primitive Fourier series method for the stationary Navier-Stokes problem in three dimensions at arbitrary Reynolds number.This research was supported by the National Science Foundation, Grant No. NSF-GP-37069.