| year of publication | ISBN | author(s) | title |
|---|---|---|---|
| 2008 | 978-0-9784570-0-6 | George J Boelcke | Colors Tools for Christians: Discovering God's gifts of our talents, strengths, and skills through personality types |
| 2009 | 978-0-9784570-1-3 | George Boelcke | Colorful Personalities: Discover Your Personality Type Through the Power of Colors: Discover Your Personality Type Through the Power of Colors |