A long time I was not sure on which date Simon & Garfunkel performed in Paris, during their 1970 tour in Europe. It was mentioned in the Billboard of May 23rd 1970:
So the date is May 3rd, 1970.
Besides that there is a very nice bootleg recording of their show, maybe there are readers in France, I am still not sure which concert hall they played. Could it have been L`Olympia? Anyway, all additional info is welcomed!
Paul Simon - 'Time it was...it was' 