APA

Mahood H. R., . (1967). Pressure groups in American politics. New York: Scribner.

Chicago

Mahood H R, . 1967. Pressure groups in American politics. New York: Scribner.

Harvard

Mahood H. R., . (1967). Pressure groups in American politics. New York: Scribner.

MLA

Mahood H R, . Pressure groups in American politics. New York: Scribner. 1967.