%0 Journal Article %A Falk, Richard S. %T Approximation of an elliptic boundary value problem with unilateral constraints %J ESAIM: Mathematical Modelling and Numerical Analysis %D 1975 %P 5-12 %V 9 %N R2 %I Dunod %C Paris %U http://geodesic.mathdoc.fr/item/M2AN_1975__9_2_5_0/ %G en %F M2AN_1975__9_2_5_0