Cyhoeddwyd yn wreiddiol = Originally published: Kevin Mayhew, 2000.
OBNB doesn't sell books, but you may be able to find a copy at one of these websites:
Cyn ei ddod by Nick Fawcett. ISBN 1859944817. Published by Cyhoeddiadau'r Gair in 2004. Publication and catalogue information, links to buy online and reader comments.
