APA Style
The world book Encyclopedia U-V.20. (2007).
Chicago:
World Book.
Chicago Style
The world book Encyclopedia U-V.20.
.
Chicago:
World Book,
2007.
Text.
MLA Style
The world book Encyclopedia U-V.20.
.
Chicago:
World Book,
2007.
Text.
Turabian Style
The world book Encyclopedia U-V.20.
Chicago:
World Book,
2007.
Print.