APA (7th ed.) Citation

Adams, I. H. (1991). The world book encyclopedia. I - Z ([9th ed.].). World Book.

Chicago Style (17th ed.) Citation

Adams, Ian Hugh. The World Book Encyclopedia. I - Z. [9th ed.]. Chicago: World Book, 1991.

MLA (9th ed.) Citation

Adams, Ian Hugh. The World Book Encyclopedia. I - Z. [9th ed.]. World Book, 1991.