Hart, H. L. A. "LEGAL RESPONSIBILITY AND EXCUSES." Punishment and Responsibility: Essays in the Philosophy of Law. : Oxford University Press, 2008-03-06. Oxford Scholarship Online. 2009-01-01. Date Accessed 22 May. 2013 <http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780199534777.001.0001/acprof-9780199534777-chapter-2>.
Hart, H.(2008-03-06). LEGAL RESPONSIBILITY AND EXCUSES. In Punishment and Responsibility: Essays in the Philosophy of Law. : Oxford University Press. Retrieved 22 May. 2013, from http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780199534777.001.0001/acprof-9780199534777-chapter-2.
Hart, H. L. A. "LEGAL RESPONSIBILITY AND EXCUSES." In Punishment and Responsibility: Essays in the Philosophy of Law. : Oxford University Press, 2008-03-06. http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780199534777.001.0001/acprof-9780199534777-chapter-2.
Hart HLA. LEGAL RESPONSIBILITY AND EXCUSES. In: Hart H, Gardner J. Punishment and Responsibility: Essays in the Philosophy of Law. Oxford University Press; 2008. http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780199534777.001.0001/acprof-9780199534777-chapter-2. Accessed May 22, 2013.