Elton, Lord
Imperial commonwealth
Collins, 1945
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Lavell, C.F.
Imperial England
Macmillan, 1919
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Hadas, Moses
Imperial Rome
Time-Life Books, 1965
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Loewe, Michael
Imperial China
Frederick A. Preager, 1965
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O`Connell, D. P.
Opinions on imperial constitutional law
The Law Book Company, 1971
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