%0 Journal Article %A V. E. Nomofilov %T Asymptotic solutions of the second order system of differential equations concentrated in a vicinity of a ray %J Zapiski Nauchnykh Seminarov POMI %D 1981 %P 170-179 %V 104 %U http://geodesic.mathdoc.fr/item/ZNSL_1981_104_a16/ %G ru %F ZNSL_1981_104_a16