Coggle, Paul, author
Teach Youeself Books, 1991
Buku Teks
Bruce, R. Robert, author
Hodder & Stoughton, 1994
Buku Teks
Bhatia, Tej K., author
Routledge, 2000
Buku Teks
Coultas, Barbara, author
Teach Yourself Books, 1990
Buku Teks
Luthuli, Albert
Collins, 1962
Buku Teks