Rourke's world of science encyclopedia vol. 9 : technology
Rourke Publishing LLC, 2009
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McNally, Rand
Atlas of world history
Rand McNally & Co, 1957
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Philip's atlas of world history
London Chancellor Press 1999,
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Philips
Atlas of world history
Chancellor Press, 1999
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McEvery, Colin
Atlas of world population history
Facts On File, 1979
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