%0 Journal Article %A Weiss, Georg S. %T Boundary monotonicity formulae and applications to free boundary problems I: The elliptic case %J Electronic journal of differential equations %D 2004 %V 2004 %U http://geodesic.mathdoc.fr/item/EJDE_2004__2004__a26/ %G en %F EJDE_2004__2004__a26