Elliott, David
Routledge, 1997
Buku Teks
Coley, David
John Wiley & Sons, 2008
Buku Teks
edited by Bob Everett, Godfrey Boyle, Stephen Peake and Janet Ramage
Oxford University Press, 2012
Buku Teks
Outhwaite, William
Blackwell, 2006
Buku Teks
Uqaili, Mohammad Aslam, editor
Springer, 2012
eBooks