| title | ISBN-13 (ISBN-10) | year of publication |
|---|---|---|
| Gravitation, electromagnetism and cosmology: Toward a new synthesis | 978-0-9683689-6-1 (0-9683689-6-4) | 2001 |
| The Cosmologist's Second: The Riddle of Time in Theories of the Universe | 978-0-940262-41-6 (0-940262-41-X) | 1991 |