World Health Organization. (1999). Sexually transmitted infections prevalence study methodology. World Health Organization.
Chicago Style (17. basım) AtıfWorld Health Organization. Sexually Transmitted Infections Prevalence Study Methodology. Geneva,Switzerland: World Health Organization, 1999.
MLA (8th ed.) AtıfWorld Health Organization. Sexually Transmitted Infections Prevalence Study Methodology. World Health Organization, 1999.
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