%0 Journal Article
%A V. A. Erovenko
%T Lacunae in the spectrum of a fourth order differenetial operator with periodic coefficients
%J Differencialʹnye uravneniâ
%D 1975
%P 1942-1948
%V 11
%N 11
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DE_1975_11_11_a3/
%G ru
%F DE_1975_11_11_a3