Arg Saesneg gwreiddiol = Original English ed: London: Heinemann, 1980. - Arg Cymraeg gwreiddiol = Original Welsh ed: 1981.
Testun ar y cloriau tu mewn = Text on inside covers.
Ble mae Smot? by Eric Hill. ISBN 0850889936. Published by Gomer in 1992. Publication and catalogue information, links to buy online and reader comments.