%0 Journal Article %A L. I. Kamynin %A B. N. Khimchenko %T On local estimates near the boundary of solutions of a~second order equation with nonnegative characteristic form %J Sbornik. Mathematics %D 1978 %P 715-735 %V 34 %N 6 %I mathdoc %U http://geodesic.mathdoc.fr/item/SM_1978_34_6_a2/ %G en %F SM_1978_34_6_a2