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I highly suggest these:
'Don't Make Me Think' and 'Rocket Surgery Made Easy' - Steve Krug
'Laws of UX: Design Principles for Persuasive and Ethical Products' - Jon Yablonski
'Design is a Job' - Mike Monterio
More of an all-things reference (and lives near my desk):
'About Face: The Essentials of Interaction Design' - Alan Cooper