%0 Journal Article %A Marco Annoni %A Emanuele Casini %T An upper bound for the Lipschitz retraction constant in $l_1$ %J Studia Mathematica %D 2007 %P 73-76 %V 180 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/sm180-1-5/ %R 10.4064/sm180-1-5 %G en %F 10_4064_sm180_1_5