%0 Journal Article %A S. E. Romanova %T Approximate methods for solving, asymptotically in one and two %J Doklady Akademii Nauk %D 1983 %P 49-54 %V 273 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/item/DAN_1983_273_1_a10/ %G ru %F DAN_1983_273_1_a10