Southern U.S. border established. (2013). The History Channel website. Retrieved 11:48, May 23, 2013, from http://www.history.com/this-day-in-history/southern-us-border-established.
Southern U.S. border established. [Internet]. 2013. The History Channel website. Available from: http://www.history.com/this-day-in-history/southern-us-border-established [Accessed 23 May 2013].
“Southern U.S. border established.” 2013. The History Channel website. May 23 2013, 11:48 http://www.history.com/this-day-in-history/southern-us-border-established.
“Southern U.S. border established,” The History Channel website, 2013, http://www.history.com/this-day-in-history/southern-us-border-established [accessed May 23, 2013].
“Southern U.S. border established,” The History Channel website, http://www.history.com/this-day-in-history/southern-us-border-established (accessed May 23, 2013).
Southern U.S. border established [Internet]. The History Channel website; 2013 [cited 2013 May 23] Available from: http://www.history.com/this-day-in-history/southern-us-border-established.
Southern U.S. border established, http://www.history.com/this-day-in-history/southern-us-border-established (last visited May 23, 2013).
Southern U.S. border established. The History Channel website. 2013. Available at: http://www.history.com/this-day-in-history/southern-us-border-established. Accessed May 23, 2013.