%0 Journal Article %A Zhidkov, Peter E. %T Sufficient conditions for functions to form Riesz bases in $L_2$ and applications to nonlinear boundary-value problems %J Electronic Journal of Differential Equations %D 2001 %V 2001 %I mathdoc %U http://geodesic.mathdoc.fr/item/EJDE_2001__2001__a37/ %G en %F EJDE_2001__2001__a37