SYSTEM FROM SEFER YETZIRA.
COMPLETE DETAILS BLOG: http://231portas.blogspot.com/
"Sefer Yetzirah, The Book of Formation" or The Book of Creation
By Aryeh Kaplan
More Sefer Yetsirah books
"Origins of Kabbalah"
By Gershom Sholem
Sepher Rezial Hemelach: The Book of the Angel Raziel (Hardcover) by Steve Savedow (Editor)