%0 Journal Article %A Przemysław Kajetanowicz %T Extreme spectral states and multiplicative extensions in Banach algebras %J Colloquium Mathematicum %D 1984 %P 111-116 %V 48 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/cm-48-1-111-116/ %R 10.4064/cm-48-1-111-116 %G en %F 10_4064_cm_48_1_111_116