Sexual Landscapes: Why We Are What We Are, Why We Love Whom We Love Paperback – Illustrated, April 13, 2013

This is not a sensational exposé. It's insightful, thorough, and well referenced. It looks like a doctoral thesis. A must-read for psychotherapists (like me) who treat clients with non-standard sexual preferences, and for those troubled by unconventional preferences or activities (like cross-dressing).