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