%0 Journal Article %A T. I. Kiguradze %T On doubly periodic solutions of a class of nonlinear hyperbolic equations %J Differencialʹnye uravneniâ %D 1998 %P 238-245 %V 34 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/item/DE_1998_34_2_a13/ %G ru %F DE_1998_34_2_a13