%0 Journal Article %A Jan Stochel %T On the Sz.-Nagy boundedness condition on abelian involution semigroups %J Colloquium Mathematicum %D 1987 %P 267-271 %V 54 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/cm-54-2-267-271/ %R 10.4064/cm-54-2-267-271 %G en %F 10_4064_cm_54_2_267_271