edited by Catherine Itzin
Oxford University Press, 1992
Buku Teks
Stone, Richard
Blackstone Press limited, 1997
Buku Teks
Barker, Lucius J.
Prentice-Hall, 1978
Buku Teks
Howells, Kerry
Sense, 2012
eBooks
Abraham, Henry J.
Oxford University Press, 1982
Buku Teks