Sastri, K.A. Nilakanta
A history of South India : from prehistoric times to the fall of Vijayanagar
Oxford University Press, 1958
 Buku Teks
Dworkin, Ronald
Law`s empire
Harvard University Press, 1986
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Griffiths, Percival, Sir, 1899-
Empire into Commonwealth
Ernest Benn, 1969
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Ohara, Daniel T
Empire burlesque
Duke University Press, 2003
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Charlesworth, M.P.
Roman empire
Oxford University Press, 1951
 Buku Teks