%0 Journal Article %A B. Ya. Zel'dovich %A M. A. Orlova %A V. V. Shkunov %T Nonstationary theory and calculation of the dilay time for four-wave wave-front reversal %J Doklady Akademii Nauk %D 1980 %P 592-594 %V 252 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/item/DAN_1980_252_3_a21/ %G ru %F DAN_1980_252_3_a21