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2. Blanchet, K. et al. Protecting essential health services in low-income and middle-income countries and humanitarian settings while responding to the COVID-19 pandemic. BMJ Glob. Health 5, e003675 (2020).
3. Stillbirth and Child Mortality Estimates (Inter-Agency Group for Child and Mortality Estimation, United Nations, 2020); https://childmortality.org
4. Global Burden of Disease Study 2017 (Institute for Health Metrics and Evaluation, Univ. Washington, 2019); http://ghdx.healthdata.org/gbd-2017
5. World Bank Country and Lending Groups (World Bank, 2020); https://datahelpdesk.worldbank.org/knowledgebase/articles/906519-world-bank-countryand-lending-groups