I was wondering who may have played at the RnR Circus but was left out of the film, or other available recordings. I have a Bootleg of the Rock and Roll Circus that has a Led Zeppelin track, Traveling Riverside Blues - although the LP called it the Original Lemon Song. I do not know if it was performed at the circus, it doesn't sound like a live performance, but then again the whole album was poor quality.

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