Traddodwyd y ddarlith yn = Lecture delivered at: Ysgol Bro Lleu, 9/11/2000.
Mis o newyddion by Bethan Jones Parry. ISBN 0901337773. Published by Cyngor Gwynedd, Adran Addysg, Diwylliant a Hamdden in 2000. Publication and catalogue information, links to buy online and reader comments.