| title | ISBN-13 (ISBN-10) | year of publica- tion | other author(s) |
|---|---|---|---|
| Anata mo dekiru hoken eigyo no tameno dokuta maketto koryakujutsu: Kakureta nizu wa hikidasuna. | 978-4-7650-1125-9 (4-7650-1125-9) | 2011 | |
| Kaigyoi ga shitte iru to tokusuru kaseida okane no jozu na nokoshikata: Jitsu wa seimei hoken de dekirundesu. | 978-4-7650-1163-1 (4-7650-1163-1) | 2012 | Makoto Uchida |