H.G. · Helen Gillespie · Helen Glaspoole · Helena Gillespie
A & C Black Publishers Ltd · CAA
| title | ISBN-13 | year of publica- tion | other author(s) |
|---|---|---|---|
| Datblygu Mathemateg: Trin Data Blwyddyn 4 | 978-1-84521-383-1 | 2010 | |
| Datblygu Mathemateg: Trin Data Blwyddyn 5 | 978-1-84521-452-4 | 2011 | |
| Handling Data: Ages 8-9 | 978-1-4081-0040-0 | 2009 | Hilary Koll · Steve Mills |
| Handling Data: Ages 9-10 | 978-1-4081-0039-4 | 2009 | Hilary Koll · Steve Mills |
| Handling Data: Ages 10-11 | 978-1-4081-0045-5 | 2009 | Hilary Koll · Steve Mills |