Beus, J. G. De
Harper & Brothers, 1953
Buku Teks
Toynbee, Arnold J.
Oxford University Press, 1957
Buku Teks
Simey, T.S.
Clarendon Press, 1946
Buku Teks
Carpenter, Allan
Facts On File, 1990
Buku Referensi
editors Charles Phillips, Alan Axelrod
Simon & Schuster Macmillan, 1996
Buku Referensi