Braucher, Robert
Foundation Press, 1977
Buku Teks
Goode, Roy
Penguin Books, 2004
Buku Teks
Stefan Vogenauer, editor
Oxford University Press, 2015
Buku Teks
Adams, Kristen David
St. Paul, MN : West Group, 2010
Buku Teks
Macintryre, Ewan
Blackstone Press, 1998
Buku Referensi