@Article{JCM-14-345,
author = {Hlaváček , I. and Křížek , M.},
title = {Optimal Interior and Local Error Estimates of a Recovered Gradient of Linear Elements on Nonuniform Triangulations},
journal = {Journal of Computational Mathematics},
year = {1996},
volume = {14},
number = {4},
pages = {345--362},
abstract = {<p style="text-align: justify;">We examine a simple averaging formula for the gradient of linear finite elements in $R^d$ whose interpolation order in the $L^q$-norm is $O(h^2)$ for $d&lt;2q$ and nonuniform triangulations. For elliptic problems in $R^2$ we derive an interior superconvergence for the averaged gradient over quasiuniform triangulations. Local error estimates up to a regular part of the boundary and the effect of numerical integration are also investigated.</p>},
issn = {1991-7139},
doi = {https://doi.org/},
url = {http://global-sci.org/intro/article_detail/jcm/9244.html}
}