%0 Journal Article %A A. A. Il'yushin %A G. S. Larionov %A A. N. Filatov %T Averaging in systems of nonlinear integro-differential equations %J Doklady Akademii Nauk %D 1969 %P 49-52 %V 188 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/item/DAN_1969_188_1_a11/ %G ru %F DAN_1969_188_1_a11