%0 Journal Article %A P.K. Lin %T Extremal properties of contraction semigroups on c0 . %J Semigroup forum %D 1996 %P 208-211 %V 53 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/item/SF_1996__53_2_135484/ %F SF_1996__53_2_135484