Mathemateg HBJ.
Kerslake, Daphne.
Welsh Joint Education Committee.Cynllun Adnoddau.
London : Collins Educational,
1995.
Arg. Saesneg gwreiddiol = Original English ed: London: Harcourt Brace Jovanovich, 1992.
Cyhoeddwyd dan nawdd Cynllun Adnoddau Cyd-bwyllgor Addysg Cymru = Published under the auspices of the Welsh Joint Education Committee Resources Project.
Mathematics