World Helalth Organization. (2007). Global age-friendly cities: A guide. World Health Organization.
Citazione stile Chigago Style (17a edizione)World Helalth Organization. Global Age-friendly Cities: A Guide. Geneva: World Health Organization, 2007.
Citatione MLA (8a ed.)World Helalth Organization. Global Age-friendly Cities: A Guide. World Health Organization, 2007.
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