%0 Journal Article %A Carlo Cecchini %A Dénes Petz %T Chain rules for canonical state extensions on von Neumann algebras %J Colloquium Mathematicum %D 1993 %P 115-119 %V 64 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/cm-64-1-115-119/ %R 10.4064/cm-64-1-115-119 %G en %F 10_4064_cm_64_1_115_119