Cita APA (7a ed.)

Heffner, R. D. (1954). History of the United States. The New American Library.

Cita Chicago Style (17a ed.)

Heffner, Richard D. History of the United States. New York: The New American Library, 1954.

Cita MLA (9a ed.)

Heffner, Richard D. History of the United States. The New American Library, 1954.

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