| title | ISBN-13 (ISBN-10) | year of publication |
|---|---|---|
| Improve Your Business: Handbook | 978-92-2-105341-5 (92-2-105341-5) | 1986 |
| Improve Your Business: Handbook and Workbook | 978-92-2-105342-2 (92-2-105342-3) | 1986 |
| Improve Your Business: Workbook/Ilo559 | 978-92-2-105340-8 (92-2-105340-7) | 1986 |