Influence: The Psychology of Persuasion http://www.amazon.com/Influence-Psychology-Persuasion-Busine... (http://www.amazon.com/Influence-Psychology-Persuasion-Business-Essentials/dp/006124189X/) The Definitive Book of Body Language http://www.amazon.com/Definitive-Book-Body-Language/dp/05538... (http://www.amazon.com/Definitive-Book-Body-Language/dp/0553804723/) +1 to How to Win Friends & Influence People
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