About five short decades ago Serge Lang had occasion to introduce "multilinear categories" in the treatment of cup products he included in his "Rapport sur la Cohomologie des Groupes," a report "written in 1959 for Bourbaki's internal consumption," and published in 1966/67 in the astonishing W.A. Benjamin series, Mathematics Lecture Notes. In his Preface, Lang speaks of this "general notion of multi- linear category" as "due to Cartier." Can anyone help me find any relevant Cartier references for this? Or did Lang mean someone other than Cartier? ... Benabou, perhaps? Or Ehresmann? Or ... ? TIA. And cheers, -- Fred [For admin and other information see: http://www.mta.ca/~cat-dist/ ]