Social Science Research Network (SSRN) Home Page
This is a place where social research studies and papers are published to share online with anyone interested on the subject. http://www.ssrn.com
Reference
Royal Geographical Society (with IBG): the heart of geography
Mapas y referencia geográfica. Expeditions training and advice. Previous expeditions reports database. http://rgs.org/HomePage.htm
Centers for Disease Control and Prevention
Center for Disease Control (USA). Asesoramiento a viajeros con recomendaciones y planes de vacunación por país. http://www.cdc.gov