S D ยท S. Dubinko
| title | ISBN-13 | year of publication |
|---|---|---|
| Practice Book 1: Office Routine | 978-9985-71-081-4 | 1998 |
| Practice Book 2: Clarity in Business Expression | 978-9985-71-082-1 | 1998 |
| Practice Book 3: Companies, Finance and Banking | 978-9985-71-083-8 | 1998 |
| Practice Book 4: Marketing and Management | 978-9985-71-084-5 | 1998 |