Black, C. E., & Helmreich, E. C. (1972). Twentieth century Europe: A history. Knopf.
Chicago Style (17th ed.) CitationBlack, Cyril Edwin, and Ernst Christian Helmreich. Twentieth Century Europe: A History. New York: Knopf, 1972.
MLA (8th ed.) CitationBlack, Cyril Edwin, and Ernst Christian Helmreich. Twentieth Century Europe: A History. Knopf, 1972.
Warning: These citations may not always be 100% accurate.
