Name	Info	Provider	Link
	subscription/membership/fee required	American Physical Society	https://link.aps.org/abstract/PRL/v100/p213901
Full text from	free resource	CORE	https://core.ac.uk/reader/9027620?utm_source=linkout
	free resource	Strathprints - the University of Strathclyde	https://strathprints.strath.ac.uk/19627/