%0 Journal Article
%A Jürgen Voigt
%T A Perturbation Theorem for the Essential Spectral Radius of Strongly Continuous Semigroups.
%J Monatshefte für Mathematik
%D 1980
%P 153-162
%V 90
%I mathdoc
%U http://geodesic.mathdoc.fr/item/MOMA_1980__90_177988/
%F MOMA_1980__90_177988