Arg. Saesneg gwreiddiol = Original English ed.: London: HarperCollins Publishers, 1997.
Addasiad Cymraeg gan = Welsh adaptation by: Sian Mererid Williams.
Un llwynog cynnes by Nick Butterworth. ISBN 1855963817. Published by Gwasg y Dref Wen in 1999. Publication and catalogue information, links to buy online and reader comments.