Argraffiad Saesneg gwreiddiol = Original English edition: Oxford : Oxford University Press, 1990.
Addasiad Cymraeg gan = Welsh adaptation by: Juli Paschalis.
Teitl o'r clawr = Title from cover.
Yr herwgipwyr by Roderick Hunt. ISBN 0861743148. Published by Gwasg Addysgol Drake in 2000. Publication and catalogue information, links to buy online and reader comments.