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WebMD Feature: "10 Surprising Health Benefits of Sex."
National Sleep Foundation: "The Sleep Environment."
MedlinePlus, The National Institutes of Health: "Sleeping Difficulty."
FamilyDoctor, American Academy of Family Physicians: "Insomnia: How to Get a Good Night's Sleep."
Barry Krakow, MD, medical director, Maimonides Sleep Arts and Sciences, Ltd., Albuquerque, N.M.; author, Sound Sleep, Sound Mind: Seven Keys to Sleeping Through the Night.
University of Maryland Sleep Disorders Center: "Sleep Hygiene: Helpful Hints to Help You Sleep."
American Academy of Sleep Medicine: "Sleep Hygiene -- The Healthy Habits of Good Sleep."
WebMD Feature: "The Best Mattress for a Good Night's Sleep."
WebMD Feature: "Snuggle Up with the Perfect Pillow."
American Academy of Sleep Medicine: "Sleep Tips for Women."
WebMD the Magazine: "Trouble Sleeping? Some Bedtime Snacks Can Help You Sleep."
American Academy of Sleep Medicine: "Insomnia Advice: Expert Q&A."
Mayo Clinic: "Types of Relaxation Techniques."
U.S. Dept of Health and Human Services Office on Women's Health: "Insomnia."