John Potter ยท P.J.
| title | ISBN-13 (ISBN-10) | year of publication |
|---|---|---|
| Gogo Loves English: Workbook 3 | 978-962-00-5103-6 (962-00-5103-3) | 2001 |
| Gogo Loves English: Workbook 5 | 978-962-00-5105-0 (962-00-5105-X) | 2001 |
| Gogo Loves English: Workbook 6 | 978-962-00-5106-7 (962-00-5106-8) | 2001 |