NASA Assists Rescue of Chilean Miners. (2013). The History Channel website. Retrieved 3:55, May 21, 2013, from http://www.history.com/speeches/nasa-assists-rescue-of-chilean-miners.
NASA Assists Rescue of Chilean Miners. [Internet]. 2013. The History Channel website. Available from: http://www.history.com/speeches/nasa-assists-rescue-of-chilean-miners [Accessed 21 May 2013].
“NASA Assists Rescue of Chilean Miners.” 2013. The History Channel website. May 21 2013, 3:55 http://www.history.com/speeches/nasa-assists-rescue-of-chilean-miners.
“NASA Assists Rescue of Chilean Miners,” The History Channel website, 2013, http://www.history.com/speeches/nasa-assists-rescue-of-chilean-miners [accessed May 21, 2013].
“NASA Assists Rescue of Chilean Miners,” The History Channel website, http://www.history.com/speeches/nasa-assists-rescue-of-chilean-miners (accessed May 21, 2013).
NASA Assists Rescue of Chilean Miners [Internet]. The History Channel website; 2013 [cited 2013 May 21] Available from: http://www.history.com/speeches/nasa-assists-rescue-of-chilean-miners.
NASA Assists Rescue of Chilean Miners, http://www.history.com/speeches/nasa-assists-rescue-of-chilean-miners (last visited May 21, 2013).
NASA Assists Rescue of Chilean Miners. The History Channel website. 2013. Available at: http://www.history.com/speeches/nasa-assists-rescue-of-chilean-miners. Accessed May 21, 2013.