Offences and Defences: Selected Essays in the Philosophy of Criminal Law. : Oxford University Press, 2007-11-08. Oxford Scholarship Online. 2009-01-01. Date Accessed 24 May. 2013 <http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780199239351.001.0001/acprof-9780199239351>.
(2007-11-08). Offences and Defences: Selected Essays in the Philosophy of Criminal Law. : Oxford University Press. Retrieved 24 May. 2013, from http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780199239351.001.0001/acprof-9780199239351.
Offences and Defences: Selected Essays in the Philosophy of Criminal Law. : Oxford University Press, 2007-11-08. http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780199239351.001.0001/acprof-9780199239351.
Gardner J. Offences and Defences: Selected Essays in the Philosophy of Criminal Law. Oxford University Press; 2007. http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780199239351.001.0001/acprof-9780199239351. Accessed May 24, 2013.