On the Quasi-Optimality in $L_\infty$ of the $\overset{\circ}{H}^1$-Projection into Finite Element Spaces*
A. H. Schatz, Lars B. Wahlbin · Mathematics of Computation · 1982
A. H. Schatz, L. B. Wahlbin, On the Quasi-Optimality in $L_\infty$ of the $\overset{\circ}{H}^1$-Projection into Finite Element Spaces*, Mathematics of Computation, Vol. 38, No. 157 (Jan., 1982), pp. 1-22