1. United Nations (2020) “World Population Ageing 2019 (ST/ESA/SER.A/444)".
2. “Health perspectives: international epidemiology of ageing”;Ward;Best Practice & Research Clinical Anaesthesiology,2011
3. “World report on ageing and health”;WHO,2015
4. “Older adults: Are they ready to adopt health-related ICT?”;Heart;International journal of medical informatics,2013
5. “Definition of an older person. Proposed working definition of an older person in Africa for the MDS Project”;Kowal;World Health Organization, Geneva, doi,2001