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2. Numbers of Elderly in Thailand 2018 from BI Power Systemhttp://www.dop.go.th/th/know/1/153
3. Thai National Health Examination Survey;Aekplakorn,2016
4. Epidemiology of hypertension in the elderly;Fotoula Babatsikou;Health Sci. J.,2010
5. Raised Blood Pressurehttp://www.who.int/gho/ncd/risk_factors/blood_pressure_prevalence_text/en/