Tignor, R. L. (2014). Worlds together, worlds apart, volume 2: From 1000 CE to the present (Fourth edition.). W. W. Norton and Company.
Chicago-viite (17. p.)Tignor, Robert L. Worlds Together, Worlds Apart, Volume 2: From 1000 CE to the Present. Fourth edition. New York ; London: W. W. Norton and Company, 2014.
MLA-viite (8. p.)Tignor, Robert L. Worlds Together, Worlds Apart, Volume 2: From 1000 CE to the Present. Fourth edition. W. W. Norton and Company, 2014.
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