This book will give you everything to get started. It is split into two parts. The first part describes what patterns are, how patterns are found and described, and how to write your own patterns. I think that it will be usefull for experienced developers and larger teams that want to write up their own patterns. The second part is more of a reference. You can find many patterns and various ways to implement them. It is something that I will use to look up details of patterns. But it will also give you inspiration to solve you problems in different ways.
Find the book at http://shop.oreilly.com/product/0636920025832.do
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