Name	Info	Provider	Link
	subscription/membership/fee required	Elsevier Science	https://linkinghub.elsevier.com/retrieve/pii/S1055-7903(09)00037-2
Full text from	free resource	CORE	https://core.ac.uk/reader/162008231?utm_source=linkout
SILVA LSU Database	free resource	SILVA	http://www.arb-silva.de/search/show/lsu/pubid/19603555