%0 Journal Article
%A O. L. Safronov
%T Emergence and disappearance of the discrete spectrum in a gap of a second-order periodic operator under decreasing perturbations with alternating signs
%J Algebra i analiz
%D 1997
%P 148-166
%V 9
%N 1
%I mathdoc
%U http://geodesic.mathdoc.fr/item/AA_1997_9_1_a5/
%G ru
%F AA_1997_9_1_a5