OK, being rather new to experiencing Zep live and everything, this question struck me while listening to "The Battle of Evermore" from the Forum show (21st June, 1977). I am curious to know who was doing the back up vocals for "The Battle of Evermore" at that show. I know that as far as the studio version is concerned, this song is a duet between Robert Plant and Sandy Denny. This question may seem a bit silly to some, but then again, I am rather new as far as experiencing Zep as a live band, is concerned. A response will be much appreciated! Thanks!