%0 Journal Article %A Ya. V. Kurylev %T On the nonlinear analogue of the WKB method and the method of the averaged lagrangian.~II %J Zapiski Nauchnykh Seminarov POMI %D 1983 %P 95-101 %V 128 %I mathdoc %U http://geodesic.mathdoc.fr/item/ZNSL_1983_128_a9/ %G ru %F ZNSL_1983_128_a9