Arden, Paul, author
Penguin, 2008
Buku Teks
Lewis, John P., author
Addison-Wesley, 1999
Buku Teks
Tennant, Kylie, author
Macmillan, [Date of publication not identified]
Buku Teks
Arnaud, A. A.
Woodhead-Faulkner, 1985
Buku Teks
Metcalf, Michael, author
Oxford University Press , 1990
Buku Teks