Name	Info	Provider	Link
Caffeine	free resource	MedlinePlus Health Information	https://medlineplus.gov/caffeine.html
	subscription/membership/fee required	Nature Publishing Group	https://doi.org/10.1054/bjoc.2000.1259
	free resource	PubMed Central	https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/10917550/
	free resource	Europe PubMed Central	https://europepmc.org/abstract/MED/10917550