Harri Parri - ci gwaetha'r byd /
Lavelle, Sheila.
Ireland, John.
Rogers, Eleri.
National Language Unit of Wales.
Caerdydd : Uned Iaith Genedlaethol Cymru CBAC,
1996.
Arg. Saesneg gwreiddiol = Original English ed.: Harlow: Longman Group, 1994
Addasiad Cymraeg gan = Welsh adaptation by: Eleri Rogers
Welsh language