| title | ISBN-13 (ISBN-10) | year of publica- tion | other author(s) |
|---|---|---|---|
| The Quest: A Search for the Grail of Immortality | 978-0-595-20124-2 (0-595-20124-5) | 2002 | Rhuddlwm Gawr |
| The Way: A Discovery of the Grail of Immortality Welsh Witchcraft and the Old Religion | 978-0-595-23125-6 (0-595-23125-X) | 2002 | |