Mayhew, Susan
Oxford University Press, 1992
Buku Referensi
Whittow, John B.
Allen Lane, 1984
Buku Referensi
Goodall, Brian
Penguin Books, 1987
Buku Referensi
edited by R.J. Johnston, Derek Gregory, Geraldine Pratt, Michael Watts
Blackwell Publishing, 2000
Buku Referensi
Moore, W. G.
Penguin Books, 1974
Buku Referensi