Name	Info	Provider	Link
Vitamin A	free resource	MedlinePlus Health Information	https://medlineplus.gov/vitamina.html
	subscription/membership/fee required	Nature Publishing Group	https://doi.org/10.1038/76523
Cited by Patents in	free resource	The Lens - Patent Citations	https://www.lens.org/lens/search/patent/list?q=citation_id:10835607