Young, L. B. (1968). Population in perspective. Oxford University Press.
Lua i Stíl Chicago (17ú heag.)Young, Louise B. Population in Perspective. New York: Oxford University Press, 1968.
Lua MLA (8ú heag.)Young, Louise B. Population in Perspective. Oxford University Press, 1968.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.