U.S. Census Bureau; Minnesota Population Center (University of Minnesota), 'Census of Population and Housing 1960 - IPUMS Subset (United States)', 2016
Water and Sanitation Program (World Bank), 'WSP Global Scaling up Handwashing Behavior Impact Evaluation, Baseline and Endline Surveys 2009-2011 (Vietnam)', 2011
General Statistical Office (GSO) (Government of Vietnam); National Institute for Hygiene and Epidemiology (NIHE), Ministry of Health (Government of Vietnam), 'Population and AIDS Indicators Survey 2005 (Vietnam)', 2011