A couple ones I've read and found quite useful: Make your contacts count http://www.amazon.com/Make-Your-Contacts-Count-Networking/dp... (http://www.amazon.com/Make-Your-Contacts-Count-Networking/dp/0814474020/) The science of influence http://www.amazon.com/Science-Influence-Anyone-Minutes-Less-... (http://www.amazon.com/Science-Influence-Anyone-Minutes-Less-ebook/dp/B000VIIE9A/)
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