OPEC enacts oil embargo. (2013). The History Channel website. Retrieved 4:17, May 24, 2013, from http://www.history.com/this-day-in-history/opec-enacts-oil-embargo.
OPEC enacts oil embargo. [Internet]. 2013. The History Channel website. Available from: http://www.history.com/this-day-in-history/opec-enacts-oil-embargo [Accessed 24 May 2013].
“OPEC enacts oil embargo.” 2013. The History Channel website. May 24 2013, 4:17 http://www.history.com/this-day-in-history/opec-enacts-oil-embargo.
“OPEC enacts oil embargo,” The History Channel website, 2013, http://www.history.com/this-day-in-history/opec-enacts-oil-embargo [accessed May 24, 2013].
“OPEC enacts oil embargo,” The History Channel website, http://www.history.com/this-day-in-history/opec-enacts-oil-embargo (accessed May 24, 2013).
OPEC enacts oil embargo [Internet]. The History Channel website; 2013 [cited 2013 May 24] Available from: http://www.history.com/this-day-in-history/opec-enacts-oil-embargo.
OPEC enacts oil embargo, http://www.history.com/this-day-in-history/opec-enacts-oil-embargo (last visited May 24, 2013).
OPEC enacts oil embargo. The History Channel website. 2013. Available at: http://www.history.com/this-day-in-history/opec-enacts-oil-embargo. Accessed May 24, 2013.