By A Mystery Man Writer
Wondering whether seven hours meets your sleep needs? Find out how much sleep people need at different ages and get practical tips to sleep better.
Sleep deprivation - Wikipedia
Sleep and Health, Healthy Schools
Is six hours of sleep enough for a 20-year-old? - Quora
How much sleep do you need ? - is 7 hours of sleep enough ?
The Americans Who Don't Get Enough Sleep - WSJ
Getting enough sleep - Thompson Citizen and Nickel Belt News
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Is 6 Hours Of Sleep Enough?
The TRUTH About How Much Sleep You REALLY Need
Is sleep overrated? Are 6 hours of sleep enough for a 19-year-old? - Quora