@article{GDZPPN002203707,
title = {Regularity of solutions of nonlinear elliptic boundary value problems.},
journal = {Journal f\"ur die reine und angewandte Mathematik},
volume = {372},
year = {1986},
pages = {1-13},
zbl = {0585.35014},
url = {http://dml.mathdoc.fr/item/GDZPPN002203707}
}
Lieberman, Gary M. Regularity of solutions of nonlinear elliptic boundary value problems.. Journal für die reine und angewandte Mathematik, Tome 372 (1986) pp. 1-13. http://gdmltest.u-ga.fr/item/GDZPPN002203707/