Is it healthy to sleep 6 hours at day? - Quora
Scientists have worked out how many hours' sleep we need. | World Economic Forum
Three quarters of Brits get less than eight hours sleep | YouGov
Sleep, Deprivation Of Just 6 Hours Increases Diabetes Risk
The secret to success is sleep. - By Dr. Carmel Harrington
17 Proven Tips to Sleep Better at Night
Distribution of sleep duration by age and sex. | Download Scientific Diagram
CDC - Data and Statistics - Sleep and Sleep Disorders
If the recommended amount of sleep is 7-8 hours a night, how come so many people survive and are just fine on only 5-6 hours of sleep? - Quora
Shut-Eye Deficit: OECD Survey Reveals Japan Most Lacking in Sleep | Nippon.com
Objective sleep assessment in >80,000 UK mid-life adults: Associations with sociodemographic characteristics, physical activity and caffeine | PLOS ONE
About 40% of Japanese adults getting less than 6 hours of sleep: survey - The Mainichi
How Much Sleep Is Enough? How Much Sleep is Too Much?
What happens if you regularly only get 3 hours of sleep per night? - Quora
Dr. Joseph Mercola - How much sleep is "enough?" | Facebook
8 Hours or 7 Hours of Sleep, What's the Difference? | SiOWfa15: Science in Our World: Certainty and Controversy
How Many Hours of Sleep are Good for Health? (from 5 to 8) | Sleep, Sleeping too much, Go to bed early
Is 5 to 6 Hours of Sleep Enough? Risks, Hacks, and More
Is six hours of sleep enough for men?
How Much Sleep Do You Need? - HelpGuide.org
How much sleep do Singaporeans get? A majority (64%) manage 6-7 hours per night
Is 5 Hours Enough Sleep? How Much Sleep Should I Get?
Short Sleep Duration Among Middle School and High School Students — United States, 2015 | MMWR
YouGov | One in three Australians not getting enough sleep
