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Nemours: “Your Digestive System.”
International Hyperhidrosis Society: “Understanding Sweat.”
Arizona State University School of Life Sciences: “The Nose Knows.”
Association for the Advancement of Wound Care: “The Skin You’re In Fun Facts.”
The Library of Congress.
Smithsonian National Museum of History: “Young or Old?”
Smithsonian National Museum of History: “Male or Female?”
Stevens, J. MIT Technology Review , published online Jan. 1, 1997.
Sexual Medicine Society of North America, Inc.
Nemours: “Male Reproductive System.”
American Society for Reproductive Medicine: “Sperm Morphology (Shape): Does it Affect Fertility?”
News Release: North Carolina State University.
Your Wild Life: “Belly Button Biodiversity.”
Ghorayshi, A. Wired , published online Nov. 10, 2014.
McDonald, J. Myths of Human Genetics , Sparky House Publishing, 2011.
Reviewed by Sabrina Felson, MD on February 15, 2017
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