| title | ISBN-13 (ISBN-10) | year of publication |
|---|---|---|
| ぐんぐん元気になる脳〈2〉ROLF’S FLUMMOXING FLABBERGASTERS gungungenkininarunou〈2〉ROLF’S FLUMMOXING FLABBERGASTERS | 978-4-577-03238-1 (4-577-03238-4) | 2006 |
| ぐんぐん元気になる脳〈3〉ROLF’S CORNY COPIA gungungenkininarunou〈3〉ROLF’S CORNY COPIA | 978-4-577-03392-0 (4-577-03392-5) | 2007 |