@article{GDZPPN001181092,
title = {Optimal L...-Error Estimates for Nonconforming and Mixed Finite Element Methods of Lowest Order.},
journal = {Numerische Mathematik},
volume = {50},
year = {1986},
pages = {587-612},
zbl = {0597.65080},
url = {http://dml.mathdoc.fr/item/GDZPPN001181092}
}
Gastaldi, Lucia; Nochetto, Ricardo. Optimal L...-Error Estimates for Nonconforming and Mixed Finite Element Methods of Lowest Order.. Numerische Mathematik, Tome 50 (1986) pp. 587-612. http://gdmltest.u-ga.fr/item/GDZPPN001181092/