%0 Journal Article %A S. Pyatkov %T Some properties of eigenfunctions of linear pencils and applications to mixed type operator-differential equations %J Banach Center Publications %D 1992 %P 373-382 %V 27 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/-27-2-373-382/ %R 10.4064/-27-2-373-382 %G en %F 10_4064__27_2_373_382