7 tips to help you quit snoring.
   https://www.webmd.com/sleep-disorders/features/easy-snoring-remedies

Information about sleep apnea.
   http://www.sleepeducation.org/essentials-in-sleep/sleep-apne a

The Association for the Study of Dreams.
   https://www.asdreams.org/

The benefits of proper sleep health.
   https://www.sleep.org/

The Better Sleep Council.
   https://bettersleep.org/

The Sleep Foundation.
   https://www.sleepfoundation.org/sleep-topics/how-sleep-works

Brain Basics: Understanding Sleep.
   https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Understanding-Sleep

Installing a waterbed mattress.
   https://www.youtube.com/watch?v=RyXmKRHvUzU

The invention and evolution of waterbeds.
   https://purple.com/mattress-types/waterbed-mattresses

Pillow Talk - My Waterbed Shop articles related to waterbeds.
   https://www.my-waterbed-shop.com/mpillow.html