Name	Info	Provider	Link
	subscription/membership/fee required	Elsevier Science	https://linkinghub.elsevier.com/retrieve/pii/S0264-410X(09)01805-2
Smallpox	free resource	MedlinePlus Health Information	https://medlineplus.gov/smallpox.html
	free resource	PubMed Central	https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/19944151/
	free resource	Europe PubMed Central	https://europepmc.org/abstract/MED/19944151
	subscription/membership/fee required	ClinicalKey	https://www.clinicalkey.com/content/playBy/pii?v=S0264-410X(09)01805-2
Cited by Patents in	free resource	The Lens - Patent Citations	https://www.lens.org/lens/search/patent/list?q=citation_id:19944151