APA
Ritchie D. A., . (2006). The Congress of the United States. Oxford: Oxford University Press.
Chicago
Ritchie Donald A, . 2006. The Congress of the United States. Oxford: Oxford University Press.
Harvard
Ritchie D. A., . (2006). The Congress of the United States. Oxford: Oxford University Press.
MLA
Ritchie Donald A, . The Congress of the United States. Oxford: Oxford University Press. 2006.