APA

Coyle D. C., . (1954). The United States political system. New York: A Signet Key Book.

Chicago

Coyle David Cushman, . 1954. The United States political system. New York: A Signet Key Book.

Harvard

Coyle D. C., . (1954). The United States political system. New York: A Signet Key Book.

MLA

Coyle David Cushman, . The United States political system. New York: A Signet Key Book. 1954.