APA
Clack G., United State Department of State, . (1997). Portrait of the USA. New York: U.S. Department of State.
Chicago
Clack George, United State Department of State, . 1997. Portrait of the USA. New York: U.S. Department of State.
Harvard
Clack G., United State Department of State, . (1997). Portrait of the USA. New York: U.S. Department of State.
MLA
Clack George, United State Department of State, . Portrait of the USA. New York: U.S. Department of State. 1997.