Nixon launches the space shuttle program. (2013). The History Channel website. Retrieved 5:56, May 19, 2013, from http://www.history.com/this-day-in-history/nixon-launches-the-space-shuttle-program.
Nixon launches the space shuttle program. [Internet]. 2013. The History Channel website. Available from: http://www.history.com/this-day-in-history/nixon-launches-the-space-shuttle-program [Accessed 19 May 2013].
“Nixon launches the space shuttle program.” 2013. The History Channel website. May 19 2013, 5:56 http://www.history.com/this-day-in-history/nixon-launches-the-space-shuttle-program.
“Nixon launches the space shuttle program,” The History Channel website, 2013, http://www.history.com/this-day-in-history/nixon-launches-the-space-shuttle-program [accessed May 19, 2013].
“Nixon launches the space shuttle program,” The History Channel website, http://www.history.com/this-day-in-history/nixon-launches-the-space-shuttle-program (accessed May 19, 2013).
Nixon launches the space shuttle program [Internet]. The History Channel website; 2013 [cited 2013 May 19] Available from: http://www.history.com/this-day-in-history/nixon-launches-the-space-shuttle-program.
Nixon launches the space shuttle program, http://www.history.com/this-day-in-history/nixon-launches-the-space-shuttle-program (last visited May 19, 2013).
Nixon launches the space shuttle program. The History Channel website. 2013. Available at: http://www.history.com/this-day-in-history/nixon-launches-the-space-shuttle-program. Accessed May 19, 2013.