%0 Journal Article %A Carlos E. Kenig %A Jill Pipher %T The Neumann problem for elliptic equations with non-smooth coefficients. %J Inventiones mathematicae %D 1993 %P 447-510 %V 113 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/item/IM_1993__113_2_144134/ %F IM_1993__113_2_144134