Nagle, John D.
Sage Publications, 1999
Buku Teks
Tocqueville, Alexis De, author
The Bantam Classic, 2000
Buku Teks
Becker, Carl L. (Carl Lotus), 1873-1945, author
Yale University Press, 1959
Buku Teks
Mackie, Gerry, author
Cambridge University Press, 2003
Buku Teks
Catt, Helena, author
Routledge , 1999
Buku Teks