In my "Recording of the Month" review of the new Jeff Beck album, I wrote that the aria "Nessun Dorma" was from Puccini's opera Tosca. It is, of course, from another Puccini opera, Turandot. Which I knew, both operas being favorites and both of which I have seen live several times.
Rats! No-one sleeps? We were _all_ sleeping!
But Beck plays the heck out of it!