Argraffiad Saesneg gwreiddiol = Original English edition : London : Orion Children's Books, 2000.
Addasiad Cymraeg gan = Welsh adaptation by : Elin Meek.
Henri Helynt a melltith y mymi by Francesca Simon. ISBN 9781845211615. Published by Y Ganolfan Astudiaethau Addysg in 2007. Publication and catalogue information, links to buy online and reader comments.