%0 Journal Article %A Boasso, Enrico %T On the spectral set of a solvable Lie algebra of operators. %J Portugaliae mathematica %D 1997 %P 85-94 %V 54 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/item/PORMA_1997__54_1_47901/ %G en %F PORMA_1997__54_1_47901