BlenderDiplom presents the new version of their Cycles Encyclopedia. Don't confuse it with Greg Zaal's Encycopedia - this is a more in-depth, paid e-book.
Gottfried Hofmann writes:
Version 1.2 of the Cycles Encyclopedia has finally been released. Since v1.0 the book got more than 30% new content, covering every aspect of Cycles in even more detail. Additional chapters on path tracing in general, normals and introductory parts for beginners are also included now. It has also been updated with the latest changes to Cycles as of Blender version 2.73a.
This book has become an everyday companion for me when doing shading work with Cycles.