Clark, Thomas D., editor
Oxford University Press, 1961
Buku Teks SO
Rae, Wesley D.
Twayne, 1967
Buku Teks
Bantam Books, 1968
Buku Teks SO
Thomas, Kenneth D.
[publisher not identified], [date of publication not identified]
Buku Klasik
Gras, Gilbert Le, author
reuters, 2002
Buku Teks