Douglas, J.F., author
Longman, 1991
Buku Teks
Zehna, Peter W., author
Prentice-Hall, 1982
Buku Teks
Oxford University Press, 1995
Buku Teks
Eisenstadt, S. N. (Shmuel Noah), author
The Woodrow Lilson Center Press, 1999
Buku Teks
Boix, Carles, author
Cambridge University Press, 2003
Buku Teks