Name Info Provider Link
subscription/membership/fee required Ediciones Doyma, S.L. http://www.elsevier.es/en/linksolver/ft/pii/S0025-7753(20)30183-4
subscription/membership/fee required Elsevier Science https://linkinghub.elsevier.com/retrieve/pii/S0025-7753(20)30183-4
H1N1 Flu (Swine Flu) free resource MedlinePlus Health Information https://medlineplus.gov/h1n1fluswineflu.html