George Washington, Spymaster: How America Outspied the British and Won the ... - Thomas B. Allen - Google Books

http://books.google.de/books?id=B1ThAAAAMAAJ&q=%E2%80%9ECulper+Ring%E2%80%9C&dq=%E2%80%9ECulper+Ring%E2%80%9C&client=firefox-a&c

Now in paperback—the award-winning National Geographic book that presents the untold story of the invisible war behind the American Revolution. A riveting tale of intrigue, spies, counterspies and secret agents, George Washington, Spymasteris a unique and…