Bradbrook, Muriel Clara, 1909-1993, author
Cambridge University Press, 1980
Buku Teks
Edwards, Philip, author
British Council by Longmans, Green, 1970
Buku Teks
Canavan, P. Joseph, author
D.C. Health and Company, 1990
Buku Teks
edited by Miguel de Beistegui, Simon Sparks
Routledge, 2000
Buku Teks
edited, Rebecca Bushnell
Blackwell Publishing, 2005
Buku Teks