%0 Journal Article %A Goriunov, Andrii %A Mikhailets, Vladimir %A Pankrashkin, Konstantin %T Formally self-adjoint quasi-differential operators and boundary-value problems %J Electronic Journal of Differential Equations %D 2013 %V 2013 %I mathdoc %U http://geodesic.mathdoc.fr/item/EJDE_2013__2013__a4/ %G en %F EJDE_2013__2013__a4