| title | ISBN-13 (ISBN-10) | year of publication |
|---|---|---|
| Kono issatsu de kangaeru chikara to hanasu chikara ga omoshiroihodo minitsuku. | 978-4-413-00906-5 (4-413-00906-1) | 2007 |
| Kono issatsu de kangaeru chikara to hanasu chikara ga omoshiroihodo mi ni tsuku: zukai ippun doriru | 978-4-413-01903-3 (4-413-01903-2) | 2009 |