%0 Journal Article %A A. M. Stepin %T Spectrum and approximation of metric automorphisms by periodic transformations %J Funkcionalʹnyj analiz i ego priloženiâ %D 1967 %P 77-80 %V 1 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/item/FAA_1967_1_2_a6/ %G ru %F FAA_1967_1_2_a6