%0 Journal Article
%A S. V. Petras
%T On a perturbation of the poles of scattering matrix for varying baundary condition
%J Zapiski Nauchnykh Seminarov POMI
%D 1981
%P 183-191
%V 117
%I mathdoc
%U http://geodesic.mathdoc.fr/item/ZNSL_1981_117_a12/
%G ru
%F ZNSL_1981_117_a12