Name	Info	Provider	Link
Vitamin D	free resource	MedlinePlus Health Information	https://medlineplus.gov/vitamind.html
	subscription/membership/fee required	Nature Publishing Group	https://doi.org/10.1038/sj.bjc.6605262
	free resource	PubMed Central	https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/19690551/
	free resource	Europe PubMed Central	https://europepmc.org/abstract/MED/19690551