Name	Info	Provider	Link
	free resource	PubMed Central	https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/21114461/
	subscription/membership/fee required	Taylor & Francis	https://www.tandfonline.com/doi/full/10.3109/10717544.2010.536269
	free resource	Europe PubMed Central	https://europepmc.org/abstract/MED/21114461