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This piece was transcribed from an out-of-copyright hymn book. Copies of the lilypond source available on request.

Cwm Rhondda, taken from the Welsh name for the Rhondda Valley, is a popular hymn tune written by John Hughes (1873–1932) in 1907.
The above text from the Wikipedia article "Cwm Rhondda" text is available under CC BY-SA 3.0.