%0 Journal Article
%A Hughes, Edward
%T Perturbation Theorems for Relative Spectral Problems
%J Canadian journal of mathematics
%D 1972
%P 72-81
%V 24
%N 1
%U http://geodesic.mathdoc.fr/articles/10.4153/CJM-1972-009-8/
%R 10.4153/CJM-1972-009-8
%F 10_4153_CJM_1972_009_8