APA

Heffner R. D., . (1960). A documentary History of the United States. New York: A Mentor Books.

Chicago

Heffner Richard D, . 1960. A documentary History of the United States. New York: A Mentor Books.

Harvard

Heffner R. D., . (1960). A documentary History of the United States. New York: A Mentor Books.

MLA

Heffner Richard D, . A documentary History of the United States. New York: A Mentor Books. 1960.