%0 Journal Article %A V. P. Rudakov %T A bilateral estimate of the norms of the solutions of a certain class of nonlinear systems %J Differencialʹnye uravneniâ %D 1970 %P 371-372 %V 6 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/item/DE_1970_6_2_a15/ %G ru %F DE_1970_6_2_a15