Keenan, Denis, author
Pitman, 1994
Buku Teks
Bradgate, Robert, author
Butterworth, 1991
Buku Teks
Keenan, Denis, author
Pitman, 1992
Buku Teks
Hodge, David, author
Sweet & Maxwell, 2010
Buku Teks
Kelly, David, author
Cavendish Pub. Lid, 1998
Buku Teks