Exxon Valdez runs aground. (2013). The History Channel website. Retrieved 1:51, May 25, 2013, from http://www.history.com/this-day-in-history/exxon-valdez-runs-aground.
Exxon Valdez runs aground. [Internet]. 2013. The History Channel website. Available from: http://www.history.com/this-day-in-history/exxon-valdez-runs-aground [Accessed 25 May 2013].
“Exxon Valdez runs aground.” 2013. The History Channel website. May 25 2013, 1:51 http://www.history.com/this-day-in-history/exxon-valdez-runs-aground.
“Exxon Valdez runs aground,” The History Channel website, 2013, http://www.history.com/this-day-in-history/exxon-valdez-runs-aground [accessed May 25, 2013].
“Exxon Valdez runs aground,” The History Channel website, http://www.history.com/this-day-in-history/exxon-valdez-runs-aground (accessed May 25, 2013).
Exxon Valdez runs aground [Internet]. The History Channel website; 2013 [cited 2013 May 25] Available from: http://www.history.com/this-day-in-history/exxon-valdez-runs-aground.
Exxon Valdez runs aground, http://www.history.com/this-day-in-history/exxon-valdez-runs-aground (last visited May 25, 2013).
Exxon Valdez runs aground. The History Channel website. 2013. Available at: http://www.history.com/this-day-in-history/exxon-valdez-runs-aground. Accessed May 25, 2013.