Duiker, W. J., & Spielvogel, J. J. (2010). World history (6th ed.). Wadsworth Cengage Learning.
Lua i Stíl Chicago (17ú heag.)Duiker, William J., agus Jackson J. Spielvogel. World History. 6th ed. Boston, MA: Wadsworth Cengage Learning, 2010.
Lua MLA (9ú heag.)Duiker, William J., agus Jackson J. Spielvogel. World History. 6th ed. Wadsworth Cengage Learning, 2010.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.