About The Ultimate Guide to the Presidents. (2013). The History Channel website. Retrieved 3:27, May 25, 2013, from http://www.history.com/shows/the-ultimate-guide-to-the-presidents/articles/about-the-ultimate-guide-to-the-presidents.
About The Ultimate Guide to the Presidents. [Internet]. 2013. The History Channel website. Available from: http://www.history.com/shows/the-ultimate-guide-to-the-presidents/articles/about-the-ultimate-guide-to-the-presidents [Accessed 25 May 2013].
“About The Ultimate Guide to the Presidents.” 2013. The History Channel website. May 25 2013, 3:27 http://www.history.com/shows/the-ultimate-guide-to-the-presidents/articles/about-the-ultimate-guide-to-the-presidents.
“About The Ultimate Guide to the Presidents,” The History Channel website, 2013, http://www.history.com/shows/the-ultimate-guide-to-the-presidents/articles/about-the-ultimate-guide-to-the-presidents [accessed May 25, 2013].
“About The Ultimate Guide to the Presidents,” The History Channel website, http://www.history.com/shows/the-ultimate-guide-to-the-presidents/articles/about-the-ultimate-guide-to-the-presidents (accessed May 25, 2013).
About The Ultimate Guide to the Presidents [Internet]. The History Channel website; 2013 [cited 2013 May 25] Available from: http://www.history.com/shows/the-ultimate-guide-to-the-presidents/articles/about-the-ultimate-guide-to-the-presidents.
About The Ultimate Guide to the Presidents, http://www.history.com/shows/the-ultimate-guide-to-the-presidents/articles/about-the-ultimate-guide-to-the-presidents (last visited May 25, 2013).
About The Ultimate Guide to the Presidents. The History Channel website. 2013. Available at: http://www.history.com/shows/the-ultimate-guide-to-the-presidents/articles/about-the-ultimate-guide-to-the-presidents. Accessed May 25, 2013.