Walker, Gilbert
William Heinemann, 1957
Buku Teks
Cross, Rod
Martin Robertson, 1982
Buku Teks SO
Tomlinson, Jim
Methuen, 1981
Buku Teks SO
edited by Tony Buxton, Paul Chapman and Paul Temple
Routledge , 1994
Buku Teks
Berry, Craig
Palgrave Macmillan, 2016
Buku Teks