%0 Journal Article %A S. A. Nazarov %T Opening of a Gap in the Continuous Spectrum of a Periodically Perturbed Waveguide %J Matematičeskie zametki %D 2010 %P 764-786 %V 87 %N 5 %I mathdoc %U http://geodesic.mathdoc.fr/item/MZM_2010_87_5_a9/ %G ru %F MZM_2010_87_5_a9