Addasiad Cymraeg gan = Welsh adaptation by : Emily Huws.
Argraffiad Saesneg gwreiddiol = Original English edition: London : Gullane Children's Books, 2002.
Owain a'r siapiau by Ian Whybrow. ISBN 1843232170. Published by Gwasg Gomer in 2003. Publication and catalogue information, links to buy online and reader comments.