THE WORLD BOOK ENCYCLOPEDIA. (1989). The world book encyclopedia: U - V. World Book.
Lua i Stíl Chicago (17ú heag.)THE WORLD BOOK ENCYCLOPEDIA. The World Book Encyclopedia: U - V. Chicago: World Book, 1989.
Lua MLA (9ú heag.)THE WORLD BOOK ENCYCLOPEDIA. The World Book Encyclopedia: U - V. World Book, 1989.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.