%0 Journal Article %A Joel Cohen %T A characterization of inner product spaces using absolutely 2-summing operators %J Studia Mathematica %D 1970 %P 271-276 %V 38 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/sm-38-1-271-276/ %R 10.4064/sm-38-1-271-276 %G en %F 10_4064_sm_38_1_271_276