Peter Paul And Mary was a mostly acoustic folk trio. Peter was Peter Yarrow, Paul was Noel Paul Stookey, and Mary was Mary Travers. The greatest hit by Peter Paul And Mary was 1969 number one song Leaving On A Jet Plane, which was written by John Denver. Previously, Peter, Paul And Mary hit number 2 with the song Puff The Magic Dragon, originally called Puff, then called Puff (The Magic Dragon), and finally called Puff The Magic Dragon. This song was co-written by Peter Yarrow with Leonard Lipton, and became the group's signature tune.