Population Reference Bureau. (1972). The world population dilemma. Columbia Books.
Lua i Stíl Chicago (17ú heag.)Population Reference Bureau. The World Population Dilemma. Washington: Columbia Books, 1972.
Lua MLA (9ú heag.)Population Reference Bureau. The World Population Dilemma. Columbia Books, 1972.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.