%0 Journal Article %A M. I. Al'mukhamedov %T The sets of periodic motions determined by a~system of differential equations %J Izvestiâ vysših učebnyh zavedenij. Matematika %D 1958 %P 5-16 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/item/IVM_1958_2_a1/ %G ru %F IVM_1958_2_a1