Gaya APA
Wittkopf, E, R., Jones, C, M. (2008).
American foreign policy: pattern and process (7th. Ed.).
Singapore:
Thomson Wadsworth.
Gaya MLA
Wittkopf, Eugene, R.., Jones, Christopher, M..
"American foreign policy: pattern and process".
7th. Ed.
Singapore:
Thomson Wadsworth,
2008.
Text.