World Health Organization. (2000). International travel and health: Vaccination requirements and health advice. World Health Organization.
Citazione stile Chigago Style (17a edizione)World Health Organization. International Travel and Health: Vaccination Requirements and Health Advice. Geneva: World Health Organization, 2000.
Citatione MLA (8a ed.)World Health Organization. International Travel and Health: Vaccination Requirements and Health Advice. World Health Organization, 2000.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.