Arg. Saesneg gwreiddiol = Original English ed.: Harlow: Longman, 1994.
Addasiad Cymraeg gan = Welsh adaptation by: Urien Wiliam.
Cadw'r lle'n daclus by David Webb. ISBN 1860853099. Published by Uned Iaith Genedlaethol Cymru in 1998. Publication and catalogue information, links to buy online and reader comments.