| title | ISBN-13 (ISBN-10) | year of publica- tion |
|---|---|---|
| The Future of Peace: On the Front Lines with the World's Great Peacemakers | 978-0-06-251742-5 (0-06-251742-2) | 2004 |
| Twice Told: Original Stories Inspired by Original Artwork | 978-0-525-46818-9 (0-525-46818-8) | 2006 |