Who wrote the song "Leaving on a Jet Plane"?

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The year 1969 was winding down and Peter, Paul and Mary found themselves watching "Leaving on a Jet Plane" climb the charts to become their biggest (and final) hit. The number one smash about a heartbroken traveler saying goodbye at the airport had come from a young singer-songwriter who had written it a few years earlier and given it away as a Christmas gift. Who penned "Leaving on a Jet Plane"?



