Argraffiad Saesneg gwreiddiol = Original English edition : London : Andersen Press, 2001.
Addasiad Cymraeg gan = Welsh adaptation by : Hedd a Non ap Emlyn.
Cwac, Cwac! by Philippe Dupasquier. ISBN 1855964899. Published by Gwasg y Dref Wen in 2001. Publication and catalogue information, links to buy online and reader comments.