Title:         Error estimates for the approximation of a class of variational 
               inequalities

Authors:       Richard S. Falk

Source:        Math. of Comp., 28 (1974), 963-971.

Status:        Published

Abstract:      In this paper, we prove a general approximation theorem 
               useful in obtaining order of convergence estimates for the
               approximation of the solutions of a class of variational 
               inequalities. The theorem is then applied to obtain an 
               "optimal" rate of convergence for the approximation of a 
               second-order elliptic problem with convex set 
               K = {v in H_0^1(Omega): v >= X a.e. in Omega }.