Gaya APA

Fund, U, N, P., International, H. (2012). Ageing in the Twenty-First Century: A Celebration and A Challenge . New York: United Nations Population Fund.

Gaya MLA

Fund, United, Nations, Population., International, HelpAge. "Ageing in the Twenty-First Century: A Celebration and A Challenge". New York: United Nations Population Fund, 2012. Hardcopy (Textbook).