https://www.nytimes.com/2019/01/28/opinion/inequality-poverty-global-aid.html

https://www.nytimes.com/2019/12/28/opinion/sunday/2019-best-year-poverty.html

https://www.who.int/tobacco/research/economics/publications/oecd_dac_pov_health.pdf

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1405857/

Health equity: challenges in low-income countries …https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2877288/