If you're under 50, Mary Travers' name won't mean much to you. She was the Mary in Peter, Paul and. If, as the NY Times obit says, P,P and M were the sex appeal of the folk era, Mary was the sex appeal of the group.
Here's a You Tube video of the three singing If I Had a Hammer, introduced by Pete Seeger, who wrote the song. You can see how the camera (and so many of us folkies) loved Mary Travers. Oh my: Mary Travers.