Bork, Robert H., author
The Free Press, 1990
Buku Teks
Barton, Jonathan R.
Routledge, 1997
Buku Teks
Scott, Andrew M., author
Holt, Rinehart & Winston, 1959
Buku Teks
edited by Philip John Davies and Fredric A. Waldstein
Manchester University Press, 1987
Buku Teks
edited by Louis W. Goodman, William M. LeoGrande, Johanna Mendelson Forman
Westview Press, 1992
Buku Teks