%0 Journal Article %A Silva, Fernando C. %T An additive inverse characteristic polynomial theorem %J Portugaliae mathematica %D 1990 %P 403-409 %V 47 %N 4 %I mathdoc %U http://geodesic.mathdoc.fr/item/PORMA_1990__47_4_115728/ %G en %F PORMA_1990__47_4_115728