1. World Bank20172017-03-01Maternal mortality ratio (modeled estimate, per 100,000 live births)
http://data.worldbank.org/indicator/SH.STA.MMRT?end=2014&locations=VN&start=1990
2. World Health Organization20152017-03-01Vietnam - maternal mortality in 1990-2015
http://www.who.int/gho/maternal_health/countries/vnm.pdf
3. Vietnam
4. General Statistics Office20112017-12-18Viet Nam population and housing census 2009: age-sex structure and marital status of the population in Viet Nam
https://www.gso.gov.vn/Modules/Doc_Download.aspx?DocID=13286
5. World Bank20112017-12-18Vietnam - multiple indicator cluster survey 2011 final report
http://microdata.worldbank.org/index.php/catalog/1308