The following books are the main books that I recommend as starting points for learning about the various aspects of Agile. While their is a fair amount of overlap each of them covers a specific topic. The one on leading self-directed teams is not strictly an "Agile" book, but it is one of the few books talking about self-managed/self-organized/self-directed teams that I have found. The Toyota way is also not an "Agile" book but does a great job of explaining the concepts of Lean which I believe are the foundation for Agile.
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