Name	Info	Provider	Link
	subscription/membership/fee required	Atypon	https://journals.asm.org/doi/10.1128/JVI.2.9.937-943.1968?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub 0pubmed
	free resource	PubMed Central	https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/4302190/
	free resource	Europe PubMed Central	https://europepmc.org/abstract/MED/4302190