APA Style
National Geographic: 100 years. (1988).
Washington, D.C.:
.
Chicago Style
National Geographic: 100 years.
.
Washington, D.C.:
,
1988.
Text.
MLA Style
National Geographic: 100 years.
.
Washington, D.C.:
,
1988.
Text.
Turabian Style
National Geographic: 100 years.
Washington, D.C.:
,
1988.
Print.