Arg Saesneg gwreiddiol = Original English ed: Hove: Wayland, 1984.
Llyfryddiaeth = Bibliography: p31. - Yn cynnwys mynegai = Includes index.
Arferion geni by Jon Mayled. ISBN 1853570567. Published by Canolfan Genedlaethol Addysg Grefyddol in 1993. Publication and catalogue information, links to buy online and reader comments.