Name	Info	Provider	Link
Tears	free resource	MedlinePlus Health Information	https://medlineplus.gov/tears.html
	free resource	PubMed Central	https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/23361507/
	free resource	Europe PubMed Central	https://europepmc.org/abstract/MED/23361507
	free resource	scite Smart Citations	https://scite.ai/reports/23361507
	subscription/membership/fee required	Silverchair Information Systems	https://iovs.arvojournals.org/article.aspx?doi=10.1167/iovs.12-10817