World Health Organization. Vaccines and Biologicals: Who vaccine-preventable diseases: monitoring system.
Cita Chicago (17th ed.)World Health Organization. Vaccines and Biologicals: Who Vaccine-preventable Diseases: Monitoring System.
Cita MLA (8th ed.)World Health Organization. Vaccines and Biologicals: Who Vaccine-preventable Diseases: Monitoring System.
Atenció: Aquestes cites poden no estar 100% correctes.