Arg. Saesneg gwreiddiol = Original English ed.: Llundain: Orchard Books, 1998.
Addasiad Cymraeg gan = Welsh adaptation by: Luned Whelan.
Teitl clawr = Cover title.
Gwenno Gwningen : rhifau by Patrick Yee. ISBN 0852842309. Published by Hughes a'i Fab in 1998. Publication and catalogue information, links to buy online and reader comments.