%0 Journal Article %A M. S. Agranovich %T Positive mixed problems for certain hyperbolic systems %J Doklady Akademii Nauk %D 1966 %P 1215-1218 %V 167 %N 6 %I mathdoc %U http://geodesic.mathdoc.fr/item/DAN_1966_167_6_a0/ %G ru %F DAN_1966_167_6_a0