%0 Journal Article %A M. T. Terekhin %T Nonzero periodic solutions of a~nonautonomous system of ordinary differential equations %J Izvestiâ vysših učebnyh zavedenij. Matematika %D 2002 %P 63-68 %N 6 %I mathdoc %U http://geodesic.mathdoc.fr/item/IVM_2002_6_a9/ %G ru %F IVM_2002_6_a9