exploration in the enneagram

I have just started exploring the enneagram. These are the websites I have been looking at:

• The Enneagram Spectrum || Jerome P. Wagner, PhD
• Enneagram Worldwide || Helen Palmer and David Daniels, M.D.
• Enneagram.com || Helen Palmer
• International Enneagram Association
• The Enneagram Institute || Don Richard Riso and Russ Hudso