World Health Organization. (1999). Reduction of maternal mortality. World health Organization.
Cita Chicago (17th ed.)World Health Organization. Reduction of Maternal Mortality. Geneva: World health Organization, 1999.
Cita MLA (8th ed.)World Health Organization. Reduction of Maternal Mortality. World health Organization, 1999.
Atenció: Aquestes cites poden no estar 100% correctes.