Name	Info	Provider	Link
	subscription/membership/fee required	Ingenta plc	https://www.ingentaconnect.com/openurl?genre=article&issn=1568-0266&volume=5&issue=8&spage=785&aulast=Zimmermann
	subscription/membership/fee required	Bentham Science Publishers Ltd.	https://www.eurekaselect.com/79369/article