Rourke's world of science encyclopedia vol. 9 : technology
Rourke Publishing LLC, 2009
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Philip's atlas of world history
London Chancellor Press 1999,
Buku Referensi
McEvery, Colin
Atlas of world population history
Facts On File, 1979
Buku Referensi
Philips
Atlas of world history
Chancellor Press, 1999
Buku Referensi
The Times atlas of world history
edited by Geoffrey Barraclough
Times Books, 1984
Buku Referensi