Academic Press · HarperCollins
| title | ISBN-13 (ISBN-10) | year of publica- tion | other author(s) |
|---|---|---|---|
| Essential Enneagram: The Definitive Personality Test and Self-Discovery Guide -- Revised & Updated | 978-0-06-171316-3 (0-06-171316-3) | 2009 | David N., M.D. Daniels |
| Type a Behavior Pattern: A Model for Research and Practice | 978-0-12-564680-2 (0-12-564680-1) | 1982 | |
A D · A. P. · Ph.D. · V. A. · V.P. · Virginia A.