Summer means more hours of daylight and for many, it contributes to trouble falling asleep. More than 40 million Americans suffer from chronic sleep disorders, resulting in $18 billion in cost to employers due to sleep loss issues.
Fuente : http://feeds.sciencedaily.com/~r/sciencedaily/~3/r...
Fuente : http://feeds.sciencedaily.com/~r/sciencedaily/~3/r...