Bibliography/References Step 4
Sources:
Leitch, I. (1942) The evolution of dietary standards. Nutr. Abs. Rev. 11:509-521
www.onlinelibrary.wiley.com/doi/10.1111/j.1753-4887.2008.00102.x/full
http://www.vitamindcouncil.org/about-vitamin-d/what-is-vitamin-d/vitamin-d-toxicity/
www.orthomolecular.org/resources/omns/v05n04.shtml
http://en.wikipedia.org/wiki/Vitamin_poisoning#cite_note-5
www.hsph.harvard.edu/nutritionsource/what-should-you-eat/vitamins/
www.jama.ama-assn.org/content/279/15/1200.full
