%0 Journal Article %A A. L. Garkavi %T On Existence of Best Approximation of a~Function of Two Variables by Sums of Plane Waves %J Informatics and Automation %D 1997 %P 130-136 %V 219 %I mathdoc %U http://geodesic.mathdoc.fr/item/TRSPY_1997_219_a10/ %G ru %F TRSPY_1997_219_a10