Macintyre, Stuart, author
Oxford University Press, 1986
Buku Teks
Graham, Loren R., author
Cambridge University Press, 1993
Buku Teks
Younger, R. M.
Rigby, 1975
Buku Teks
Nicholson, D.F., author
F.W. Cheshire, 1955
Buku Teks
Molony, John
Viking, 1987
Buku Teks