Peter Yarrow, one of the principal singers of the seminal 1960s folk trio Peter, Paul and Mary, has died of bladder cancer ... mostly folk standards and Pete Seeger songs, found great success.

Yarrow died of bladder cancer, according to the representative ... included the hit singles "Lemon Tree" and a cover of the Pete Seeger standard "If I Had a Hammer (The Hammer Song)." ...

Peter Yarrow — the singer-songwriter best known as one-third of Peter, Paul and Mary — died on Tuesday in New York at the age ...