The Pennywhistlers were an American singing group founded by folklorist and singer Ethel Raim and popular during the 1960s folk music revival.
They specialized in Eastern European polyphonic vocal music, traditional and arranged, sung primarily a cappella.
Folk singer Theodore Bikel, in his autobiography Theo, called them "the closest to the real thing in authenticity in the United States.
They shared the bill with performers such as Bob Dylan, Pete Seeger, Joan Baez, Reverend Gary Davis, Leonard Cohen, and many others.
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