APA Style
The World Book Encyclopedia 21: W. X. Y. Z. (1995).
Chicago:
World Book International.
Chicago Style
The World Book Encyclopedia 21: W. X. Y. Z.
.
Chicago:
World Book International,
1995.
Text.
MLA Style
The World Book Encyclopedia 21: W. X. Y. Z.
.
Chicago:
World Book International,
1995.
Text.
Turabian Style
The World Book Encyclopedia 21: W. X. Y. Z.
Chicago:
World Book International,
1995.
Print.