Ten safety tips for taking sleeping pills for insomnia. American Academy of Sleep Medicine. http://www.sleepeducation.org/news/2013/01/10/ten-safety-tips-for-taking-sleeping-pills-for-insomnia. Updated August 7, 2013. Accessed June 7, 2016.
Melatonin. Memorial Sloan-Kettering Cancer Center. https://www.mskcc.org/cancer-care/integrative-medicine/herbs/melatonin. Updated July 11, 2013. Accessed May 2016.
Safe use of sleep aids. National Sleep Foundation. https://sleepfoundation.org/insomnia/content/safe-use-sleep-aids. Accessed June 7, 2016.