The Mabinogion: The Red Book of Hergest (Forgotten Books)
About the Author:"Lady Charlotte Elizabeth Guest, (née Bertie) (May 19, 1812 – January 15, 1895), was a British translator and businesswoman. An important figure in the study of Welsh literature and the Welsh language, she is best known for her pioneering translation of the major medieval work, the Mabinogion."(Quote from wikipedia.org)