%0 Journal Article %A I. A. Rudakov %T Periodic Solutions of a Nonlinear Wave Equation with Nonconstant Coefficients %J Matematičeskie zametki %D 2004 %P 427-438 %V 76 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/item/MZM_2004_76_3_a11/ %G ru %F MZM_2004_76_3_a11