%0 Journal Article %A Yu. V. Pokornyi %A S. V. Smitskikh %T Inversion of the oscillatory property of focusing operators %J Matematičeskie zametki %D 1976 %P 753-760 %V 20 %N 5 %I mathdoc %U http://geodesic.mathdoc.fr/item/MZM_1976_20_5_a15/ %G ru %F MZM_1976_20_5_a15