Name	Info	Provider	Link
	subscription/membership/fee required	Ovid Technologies, Inc.	http://ovidsp.ovid.com/ovidweb.cgi?T=JS&PAGE=linkout&SEARCH=17558546.ui
	subscription/membership/fee required	Springer	https://doi.org/10.1007/s10482-007-9166-2
SILVA SSU Database	free resource	SILVA	http://www.arb-silva.de/search/show/ssu/pubid/17558546