Supperstone, Michael
Longman, 1994
Buku Teks
Goldstein, Paul
Little, Brown, 1989
Buku Teks
Garner, W. Michael
Clark Boardman callaghan, 1994
Buku Teks
Ding, Julian
Swett and Maxwell Asia, 1999
Buku Teks
Addison, Neil
Blackstone Press Limited, 1998
Buku Teks