Ebenstein, William, author
Thomson Learning, 2000
Buku Teks
David Boucher, Paul Kelly, editor
Oxford Univesity Press, 2009
Buku Teks
edited by Isaac Kramnick
[publisher not identified], 1969
Buku Teks
Barnes & Noble, 1949
Buku Teks
Baradat, Leon P., author
Prentice-Hall, 1991
Buku Teks