Oxford University Press, 2009
Buku Referensi
Curzon, L. B., author
Pitman, 1994
Buku Referensi
editor, Elizabeth A. Martin
Oxford University Press, 1994
Buku Referensi
Harris, Phil, author
Weidenfeld and Nicolson, 1993
Buku Teks
Jennings, Ivor, Sir, 1903-1965, author
Hodder and Stoughton, 1979
Buku Teks