Arg Saesneg gwreiddiol = Original English ed: Oxford : Oxford University Press, 1992.
Yn cynnwys mynegai = Includes index.
Y ddaear by Peter Whitehead. ISBN 0905345835. Published by Cyd-bwyllgor Addysg Cymru mewn cydweithrediad â Gwasg Prifysgol Rhydychen in 1994. Publication and catalogue information, links to buy online and reader comments.