%0 Journal Article %A John Papadakis %T A Boundary value Problem for Equations of mixed type %J Ευκλείδης Γ %D 1987 %P 157-171 %V 14 %I mathdoc %U http://geodesic.mathdoc.fr/item/EUG_1987__14_a16/ %G gr %F EUG_1987__14_a16