Routledge, 1997
Buku Teks
McAvinia, Claire
Chandos Publishing, an imprint of Elsevie, 2016
Buku Teks
Her Majesty's Stationery Office, 1987
Buku Teks
edited by Maria Slowey, David Watson
Open University Press, 2003
Buku Teks
Smith, Huston
Harper & Brothers, 1955
Buku Teks