Related articles:
Effective Napping Can Boost Memory, Productivity
Nap Your Way to the Top
ABC News: Why You Need to Take a Nap at Work
CNN.com: Sleeping at work -- more of us are doing it
Sleep studies:
Study: Naps may cut heart deaths (article1, article2)
"Power Nap" Prevents Burnout; Morning Sleep Perfects a Skill
Read more from the American Academy of Sleep Medicine.