@article{GDZPPN001172735,
title = {Sard Kernel Theorems on Triangular Domains with Application to Finite Element Error Bounds.},
journal = {Numerische Mathematik},
volume = {25},
year = {1975},
pages = {215-230},
zbl = {0304.65076},
url = {http://dml.mathdoc.fr/item/GDZPPN001172735}
}
Barnhill, R.E.; Gregory, J.A. Sard Kernel Theorems on Triangular Domains with Application to Finite Element Error Bounds.. Numerische Mathematik, Tome 25 (1975) pp. 215-230. http://gdmltest.u-ga.fr/item/GDZPPN001172735/