%0 Journal Article %A B. S. Kashin %T Lower Bounds for $n$-Term Approximations of Plane Convex Sets and Related Topics %J Matematičeskie zametki %D 2002 %P 509-515 %V 72 %N 4 %I mathdoc %U http://geodesic.mathdoc.fr/item/MZM_2002_72_4_a3/ %G ru %F MZM_2002_72_4_a3