APA (7 वां संस्करण) प्रशस्ति पत्र

Palmer, A. W. (1999). The Penguin dictionary of twentieth-century history (5th ed.). Penguin Books.

शिकागो शैली (17वां संस्करण) प्रशस्ति पत्र

Palmer, Alan Warwick. The Penguin Dictionary of Twentieth-century History. 5th ed. Harmondsworth, Middlesex, England ; New York, N.Y., U.S.A.: Penguin Books, 1999.

एमएलए (8वां संस्करण) प्रशस्ति पत्र

Palmer, Alan Warwick. The Penguin Dictionary of Twentieth-century History. 5th ed. Penguin Books, 1999.