World Health Organization. (1999). Sexually transmitted infections prevalence study methodology. World Health Organization.
Cita Chicago Style (17a ed.)World Health Organization. Sexually Transmitted Infections Prevalence Study Methodology. Geneva,Switzerland: World Health Organization, 1999.
Cita MLA (8a ed.)World Health Organization. Sexually Transmitted Infections Prevalence Study Methodology. World Health Organization, 1999.
Precaución: Estas citas no son 100% exactas.