%0 Journal Article %A K. I. Oskolkov %T Linear and Nonlinear Methods of Relief Approximation %J Contemporary Mathematics. Fundamental Directions %D 2007 %P 126-148 %V 25 %I mathdoc %U http://geodesic.mathdoc.fr/item/CMFD_2007_25_a10/ %G ru %F CMFD_2007_25_a10