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Diana Lary (2012). Chinese Migrations: The Movement of People, Goods, and Ideas over Four Millennia. Rowman & Littlefield. pp. 53–55. ISBN9780742567658. "In China a little later there were massive southward refugees movements, as the Mongols came into China from the north. The flight movements as the Mongols were fruitless in escaping from the Mongols, who soon brought all of China under their control, but the refugee movements accelerated the process of northern people filling up lands to the south of the Yangzi. The Mongol conquest had the unexpected consequence of consolidating northern settlement into the south."
Frazier, I., "Invaders: Destroying Baghdad," New Yorker Magazine, [Special edition: Annals of History], April 25, 2005, Online IssueArchived 2018-06-12 at the Wayback Machine
Frazier, I., "Invaders: Destroying Baghdad," New Yorker Magazine, [Special edition: Annals of History], April 25, 2005, Online IssueArchived 2018-06-12 at the Wayback Machine
