An American tops Everest. (2013). The History Channel website. Retrieved 7:54, May 21, 2013, from http://www.history.com/this-day-in-history/an-american-tops-everest.
An American tops Everest. [Internet]. 2013. The History Channel website. Available from: http://www.history.com/this-day-in-history/an-american-tops-everest [Accessed 21 May 2013].
“An American tops Everest.” 2013. The History Channel website. May 21 2013, 7:54 http://www.history.com/this-day-in-history/an-american-tops-everest.
“An American tops Everest,” The History Channel website, 2013, http://www.history.com/this-day-in-history/an-american-tops-everest [accessed May 21, 2013].
“An American tops Everest,” The History Channel website, http://www.history.com/this-day-in-history/an-american-tops-everest (accessed May 21, 2013).
An American tops Everest [Internet]. The History Channel website; 2013 [cited 2013 May 21] Available from: http://www.history.com/this-day-in-history/an-american-tops-everest.
An American tops Everest, http://www.history.com/this-day-in-history/an-american-tops-everest (last visited May 21, 2013).
An American tops Everest. The History Channel website. 2013. Available at: http://www.history.com/this-day-in-history/an-american-tops-everest. Accessed May 21, 2013.