1. The hallmarks of aging;López-Otín;Cell,2013
2. Department of Economic and Social Affairs, Population Division;Nations;World population prospects 2019: Highlights,2019
3. Department of Economic and Social Affairs, Population Division;World Population Ageing,2015
4. World Health Organization. World report on ageing and health. (2015).
5. The world report on ageing and health;Beard;Gerontologist,2016