%0 Journal Article
%A S. Ya. Yakubov
%T Multiple completeness in the sense of M.\,V.~Keldysh of root functions of elliptic boundary value problems with a~polynomial spectral parameter
%J Izvestiya. Mathematics 
%D 1987
%P 413-420
%V 28
%N 2
%I mathdoc
%U http://geodesic.mathdoc.fr/item/IM2_1987_28_2_a7/
%G en
%F IM2_1987_28_2_a7