Name Info Provider Link
subscription/membership/fee required Ediciones Doyma, S.L. http://www.elsevier.es/en/linksolver/ft/ivp/0025-7753/128/52
subscription/membership/fee required Elsevier Science https://linkinghub.elsevier.com/retrieve/pii/S0025-7753(07)72485-5
HIV free resource MedlinePlus Health Information https://medlineplus.gov/hiv.html