Oklahoma enters the Union. (2013). The History Channel website. Retrieved 7:51, May 23, 2013, from http://www.history.com/this-day-in-history/oklahoma-enters-the-union.
Oklahoma enters the Union. [Internet]. 2013. The History Channel website. Available from: http://www.history.com/this-day-in-history/oklahoma-enters-the-union [Accessed 23 May 2013].
“Oklahoma enters the Union.” 2013. The History Channel website. May 23 2013, 7:51 http://www.history.com/this-day-in-history/oklahoma-enters-the-union.
“Oklahoma enters the Union,” The History Channel website, 2013, http://www.history.com/this-day-in-history/oklahoma-enters-the-union [accessed May 23, 2013].
“Oklahoma enters the Union,” The History Channel website, http://www.history.com/this-day-in-history/oklahoma-enters-the-union (accessed May 23, 2013).
Oklahoma enters the Union [Internet]. The History Channel website; 2013 [cited 2013 May 23] Available from: http://www.history.com/this-day-in-history/oklahoma-enters-the-union.
Oklahoma enters the Union, http://www.history.com/this-day-in-history/oklahoma-enters-the-union (last visited May 23, 2013).
Oklahoma enters the Union. The History Channel website. 2013. Available at: http://www.history.com/this-day-in-history/oklahoma-enters-the-union. Accessed May 23, 2013.