Butterfield, H. S. (1960). International conflict in the twentieth century: A Christian view. Greenwood Press.
Lua i Stíl Chicago (17ú heag.)Butterfield, Herbert Sir. International Conflict in the Twentieth Century: A Christian View. New York: Greenwood Press, 1960.
Lua MLA (9ú heag.)Butterfield, Herbert Sir. International Conflict in the Twentieth Century: A Christian View. Greenwood Press, 1960.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.