Andrews, William G.
D.van Nostrand Company,Inc., 1968
Buku Teks
Petra Dobner, Martin Loughlin, editors
Oxford University Press, 2012
Buku Teks
Toynbee, Arnold J., translator
Osford University Press, 1969
Buku Teks
Hardin, Russell
Oxford University Press, 1999
Buku Teks
Graber, Mark A.
Oxford University Press, 2015
Buku Teks