Knight, C. (2004). Civilization one: The world is not as you thought it was. Watkins Pub.
Chicago-viite (17. p.)Knight, Christopher. Civilization One: The World Is Not as You Thought It Was. London: Watkins Pub, 2004.
MLA-viite (9. p.)Knight, Christopher. Civilization One: The World Is Not as You Thought It Was. Watkins Pub, 2004.
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