APA
United Nations Centre for Social Developemnt and Humanitarian Affairs, United Nations Centre for Social Developemnt and Humanitarian Affairs, . (1991). World ageing situation. New: York UN.
Chicago
United Nations Centre for Social Developemnt and Humanitarian Affairs, United Nations Centre for Social Developemnt and Humanitarian Affairs, . 1991. World ageing situation. New: York UN.
Harvard
United Nations Centre for Social Developemnt and Humanitarian Affairs, United Nations Centre for Social Developemnt and Humanitarian Affairs, . (1991). World ageing situation. New: York UN.
MLA
United Nations Centre for Social Developemnt and Humanitarian Affairs, United Nations Centre for Social Developemnt and Humanitarian Affairs, . World ageing situation. New: York UN. 1991.