Gallup, G. H. (1972). The Gallup Poll: Public opinion, 1935-1971. Random House.
Chicago Style aipamenaGallup, George Horace. The Gallup Poll: Public Opinion, 1935-1971. New York: Random House, 1972.
MLA aipamenaGallup, George Horace. The Gallup Poll: Public Opinion, 1935-1971. Random House, 1972.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.