%0 Journal Article
%A A. P. Buslaev
%A V. M. Tikhomirov
%T Spectra of nonlinear differential equations and widths of Sobolev classes
%J Sbornik. Mathematics
%D 1992
%P 427-446
%V 71
%N 2
%I mathdoc
%U http://geodesic.mathdoc.fr/item/SM_1992_71_2_a10/
%G en
%F SM_1992_71_2_a10