Kenny, Anthony, author
Blackwell Publishing, 2007
Buku Teks
edited by John K. Ryan
The Catholic University of America Press, 1963
Buku Teks
Bentley, John Edward, author
Littlefield, Adams, 1958
Buku Teks
Mayer, Frederick, author
American Book Company, 1950
Buku Teks
edited by John Cottingham
Blackwell, 2008
Buku Teks