%0 Journal Article %A A. A. Lokshin %T Fundamental solutions of wave operators with retarded time. New asymptotic formulas %J Doklady Akademii Nauk %D 1979 %P 812-814 %V 247 %N 4 %I mathdoc %U http://geodesic.mathdoc.fr/item/DAN_1979_247_4_a11/ %G ru %F DAN_1979_247_4_a11