| title | ISBN-13 (ISBN-10) | year of publication |
|---|---|---|
| From Naked Ape to Superspecies: Humanity and the Global Eco-Crisis | 978-1-55365-031-7 (1-55365-031-X) | 2004 |
| Good News for a Change: How Everyday People Are Helping the Planet | 978-1-55054-926-3 (1-55054-926-X) | 2003 |