%0 Journal Article %A K. S. Sibirskii %T Invariants of linear representations of the rotation group of the plane and the problem of the center %J Doklady Akademii Nauk %D 1963 %P 497-500 %V 151 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/item/DAN_1963_151_3_a5/ %G ru %F DAN_1963_151_3_a5