edited by Angela Partington
Oxford University Press, 1993
Buku Referensi
edited by A. Norman Jeffares and Martin Gray
HarperCollins, 1995
Buku Referensi
Browning, D.C.
J.M. Dent & Sons, 1951
Buku Referensi
Oxford University
London, Oxford University Press
Buku Referensi
Sharpe, Gareth
Guinness Publishing, 1994
Buku Referensi