Citazione Stile APA (7a Edizione)

THE WORLD BOOK ENCYCLOPEDIA. (1989). The world book encyclopedia: U - V. World Book.

Citazione stile Chigago Style (17a edizione)

THE WORLD BOOK ENCYCLOPEDIA. The World Book Encyclopedia: U - V. Chicago: World Book, 1989.

Citatione MLA (9a ed.)

THE WORLD BOOK ENCYCLOPEDIA. The World Book Encyclopedia: U - V. World Book, 1989.