Name	Info	Provider	Link
	subscription/membership/fee required	Ediciones Doyma, S.L.	http://www.elsevier.es/en/linksolver/ft/pii/S0212-6567(18)30076-3
	free resource	Elsevier Science	https://linkinghub.elsevier.com/retrieve/pii/S0212-6567(18)30076-3
	free resource	PubMed Central	https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/31174917/
Full Text at the institutional repository	free resource	Andalusian Health Repository	http://hdl.handle.net/10668/14088
	free resource	Europe PubMed Central	https://europepmc.org/abstract/MED/31174917