%0 Journal Article
%T Sub-elliptic boundary value problems for quasilinear elliptic operators
%A Dian K. Palagachev
%A Peter R. Popivanov
%J Electronic Journal of Differential Equations
%D 1997
%I Texas State University
%X $C^{2+alpha}(overline{Omega})$ is proved for the oblique derivative problem $$cases{ a^{ij}(x)D_{ij}u + b(x,,u,,Du)=0 & in $Omega$,cr partial u/partial ell =varphi(x) & on $partial Omega$cr} $$ in the case when the vector field $ell(x)=(ell^1(x),ldots,ell^n(x))$ is tangential to the boundary $partial Omega$ at the points of some non-empty set $Ssubsetpartial Omega$, and the nonlinear term $b(x,,u,,Du)$ grows quadratically with respect to the gradient $Du$.
%K Quasilinear elliptic operator
%K degenerate oblique derivative problem
%K sub-elliptic estimates.
%U http://ejde.math.txstate.edu/Volumes/1997/01/abstr.html