%0 Journal Article %A V. A. Yudin %T Coverings of a sphere, and extremal properties of orthogonal polynomials %J Diskretnaya Matematika %D 1995 %P 81-88 %V 7 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/item/DM_1995_7_3_a7/ %G ru %F DM_1995_7_3_a7