Esposito, Vincnet
A concise history of world war
Praeger, 1965
Buku Teks SO
A concise history of world war II
Buku Teks
McEvery, Colin
Atlas of world population history
Facts On File, 1979
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Cipolla, Carlo M.
The economic history of world population
Penguin, 1974
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Birmingham, David
A concise history of Portugal
Cambridge University Press, 1993
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