Addasiad Cymraeg gan Awdurdod Cymwysterau, Cwricwlwm ac Asesu Cymru = Welsh adaptation by Qualifications, Curriculum and Assessment Authority for Wales.
Argraffiad Saesneg gwreiddiol = Original English edition : Oxford : Rigby, 1999.
Ffocws rhifedd 4 : llyfr ymarfer by L. J. Frobisher. ISBN 094846982X. Published by Gwasg Taf in 2001. Publication and catalogue information, links to buy online and reader comments.