Name	Info	Provider	Link
	free resource	Elsevier Science	https://linkinghub.elsevier.com/retrieve/pii/S0002-9165(23)04173-4
COPD	free resource	MedlinePlus Health Information	https://medlineplus.gov/copd.html
	free resource	PubMed Central	https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/27146652/
	free resource	Europe PubMed Central	https://europepmc.org/abstract/MED/27146652
	free resource	scite Smart Citations	https://scite.ai/reports/27146652
	subscription/membership/fee required	Silverchair Information Systems	https://academic.oup.com/ajcn/article-lookup/doi/10.3945/ajcn.115.125187