Blackwell, 1993
Buku Teks
edited, Peter Catterall
Institute of Contemporary British History, 1990
Buku Teks
Griffin, Gabriele, author
Cambridge University Press, 2003
Buku Teks
The Stationery Office, 1999
Buku Teks
Richmond, I.A., author
Penguin Books, 1955
Buku Teks