We consider triangulations formed by triangular elements. For the standard linear interpolation operator $\pi__h$ we prove the interpolation order to be $\left\|v-{\pi__h} v\right\|_{1,p}\leq Ch\left|v\right|_{2,p}$ for $p>1$ provided the corresponding family of triangulations is only semiregular. In such a case the well-known Zlámal's condition upon the minimum angle need not be satisfied.
@article{104461, author = {Michal K\v r\'\i \v zek}, title = {On semiregular families of triangulations and linear interpolation}, journal = {Applications of Mathematics}, volume = {36}, year = {1991}, pages = {223-232}, zbl = {0728.41003}, mrnumber = {1109126}, language = {en}, url = {http://dml.mathdoc.fr/item/104461} }
Křížek, Michal. On semiregular families of triangulations and linear interpolation. Applications of Mathematics, Tome 36 (1991) pp. 223-232. http://gdmltest.u-ga.fr/item/104461/
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