(2002). Vacines and Biologicals Who vaccine preventable diasease monitoring system 2002 global summary.
Chicago-referens (17:e uppl.)Vacines and Biologicals Who Vaccine Preventable Diasease Monitoring System 2002 Global Summary. 2002.
MLA-referens (9:e uppl.)Vacines and Biologicals Who Vaccine Preventable Diasease Monitoring System 2002 Global Summary. 2002.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.