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Book of Fiv e Rings, Miyamoto Musashi's Classic Book of Strategy (edition 1994)
Musashi's Book of Five Rings: The Definitive Interpretation of Miyamoto Musashi's Classic Book of Strategy by Stephen F. Kaufman
References to this work on external resources.
Wikipedia in English
Often used to explain Japanese business competition, 'Musashi's 'Book of Five Rings' is more properly a definitive treatise on mortal combat from one of Japan's most formidable warriors - the martial arts luminary, Miyamoto Musashi.
(summary from another edition)