APA (7th ed.) Zitazioa
World Book, Inc. (1992). The World Book Encyclopedia: W-X-Y-Z - Volume -21. World Book, Inc.
Chicago Style (17th ed.) Zitazioa
World Book, Inc. The World Book Encyclopedia: W-X-Y-Z - Volume -21. Chicago: World Book, Inc, 1992.
MLA (9th ed.) Zitazioa
World Book, Inc. The World Book Encyclopedia: W-X-Y-Z - Volume -21. World Book, Inc, 1992.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.