Henri helynt a'r clwb dirgel /
Simon, Francesca.
Lewis, Siân,1945-
Ross, Tony.
University of Wales, Aberystwyth.Centre for Educational Studies.
Aberystwyth : Y Ganolfan Astudiaethau Addysg,
2006.
Argraffiad Saesneg gwreiddiol = Original English edition : London : Orion Children's Books, 1995.
Addasiad Cymraeg gan = Welsh adaptation by : Siân Lewis.
Horrid Henry (Fictitious character)
Children's stories, Welsh.