DG3 Reference guide
This book do not try to learn you how to use DG3, it simply lists all technologies in the system, what they can do and how they works. It is meant as a side companion to look up how to use and the syntax for each technology. Each document is self contained and can be read in any order. If bases on another document, that will be listed in the reference part part with a direct link to the document with information.
If you are after learning DG3, please check out DG3 by Example instead.