Sian Griffiths & Paul Kelley 
Body Clocks: The biology of time for sleep, education and work [EPUB ebook] 

Our body’s clocks make the difference between happiness and depression, health and illness, and even life and death. The brilliant scientist Paul Kelley makes a compelling case for all organisations to allow people to work and study the hours that suit their personal circadian rhythms. That way, Paul argues, we would all be more productive, a great deal of ill health would be avoided and the world would be a better and happier place.