Name	Info	Provider	Link
	free resource	Medicina Oral S.L.	http://www.medicinaoral.com/medoralfree01/aop/21281.pdf
	free resource	PubMed Central	https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/27475700/
	free resource	Europe PubMed Central	https://europepmc.org/abstract/MED/27475700