%0 Journal Article %A Beitia, Maria Asunción %T Matrices which commute with a given matrix upon a subspace %J Portugaliae mathematica %D 1985 %P 167-178 %V 43 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/item/PORMA_1985__43_1_114496/ %G en %F PORMA_1985__43_1_114496