| title | ISBN-13 (ISBN-10) | year of publica- tion | other author(s) |
|---|---|---|---|
| Abacus: Assessment Bank Level 1 | 978-1-85356-516-8 (1-85356-516-4) | 1995 | etc. |
| Abacus: Level 1 and Level 2 Complete Set | 978-1-85356-170-2 (1-85356-170-3) | 1993 | Pip Hardy · Hugh Parker Hillyard · Anne Rooney |