Name	Info	Provider	Link
Full text from	free resource	CORE	https://core.ac.uk/reader/77002994?utm_source=linkout
	subscription/membership/fee required	Silverchair Information Systems	https://pubs.aip.org/aip/jcp/article-lookup/doi/10.1063/1.4907370
	free resource	Spiral, Imperial College Digital Repository	http://hdl.handle.net/10044/1/25397