The singer-songwriter and social activist best known as one-third of the folk-music group Peter, Paul and Mary, has died at age 86.

Peter Yarrow, one third of the chart-topping 1960s folk trio Peter, Paul and Mary and co-writer of 'Puff,the Magic Dragon' has died.

Peter, Paul and Mary performed the song at the 1963 civil rights March on Washington, cementing its place in the folk activist canon. Their version of the progressive protest song "If I Had a Hammer" -- written by Pete Seeger and Lee Hays -- earned the ...

Peter Yarrow, who has died aged 86, was the Peter in Peter, Paul and Mary, the American singing trio which took folk music into the commercial mainstream in the 1960s.

Peter Yarrow, namesake folk singer of the legendary trio Peter, Paul and Mary, has died, according to multiple reports. He was 86.

Peter Yarrow, one of the principal singers of the seminal 1960s folk trio Peter, Paul and Mary, has died of bladder cancer, The New York Times reports. He was 86 years old. Yarrow was born in New York,

Peter Yarrow -- one third of the beloved folk trio Peter, Paul and Mary ... protest song "If I Had a Hammer" -- written by Pete Seeger and Lee Hays -- earned the trio two of their five Grammy ...

of the 1960's era musical trio "Peter Paul and Mary," performs during a memorial tribute concert for folk icon and civil rights activist Pete Seeger in New York on July 20, 2014. (AP Photo/Kathy ...

The singer and songwriter who helped popularize folk music in the 1960s died of bladder cancer at his home in New York.

of the 1960’s era musical trio “Peter Paul and Mary,” performs during a memorial tribute concert for folk icon and civil rights activist Pete Seeger in New York on July 20, 2014.

Yarrow was one-third of the folk trio Peter, Paul and Mary. Peter Yarrow ... the hit singles "Lemon Tree" and a cover of the Pete Seeger standard "If I Had a Hammer (The Hammer Song)."

Peter Yarrow, who helped make folk music a pop phenomenon in the 1960s as one-third of the vocal trio Peter, Paul and Mary ... harmonized renditions of Pete Seeger’s “If I Had a Hammer ...