Arg. Saesneg gwreiddiol = Original English ed.: [Toronto]: Annick Press, 1985.
Addasiad Cymraeg gan = Welsh adaptation by: Iwan Llwyd.
Siwt eira Tomos by Robert N. Munsch. ISBN 095332060X. Published by Houdmont in 1998. Publication and catalogue information, links to buy online and reader comments.