edited by, Alan D. Burnett and Peter J. Taylor
John Wiley & Sons, 1981
Buku Teks
East, W. Gordon
Methuen, 1950
Buku Teks
Glassner, Martin Ira
Unwin Hyman, 1990
Buku Teks
Cox, Kevin R.
Blackwell, 2002
Buku Teks
Herbert, David T.
John Wiley & Sons, 1982
Buku Teks