Mankind and Engineering. (2013). The History Channel website. Retrieved 12:37, May 22, 2013, from http://www.history.com/shows/america-the-story-of-us/videos/playlists/.
Mankind and Engineering. [Internet]. 2013. The History Channel website. Available from: http://www.history.com/shows/america-the-story-of-us/videos/playlists/ [Accessed 22 May 2013].
“Mankind and Engineering.” 2013. The History Channel website. May 22 2013, 12:37 http://www.history.com/shows/america-the-story-of-us/videos/playlists/.
“Mankind and Engineering,” The History Channel website, 2013, http://www.history.com/shows/america-the-story-of-us/videos/playlists/ [accessed May 22, 2013].
“Mankind and Engineering,” The History Channel website, http://www.history.com/shows/america-the-story-of-us/videos/playlists/ (accessed May 22, 2013).
Mankind and Engineering [Internet]. The History Channel website; 2013 [cited 2013 May 22] Available from: http://www.history.com/shows/america-the-story-of-us/videos/playlists/.
Mankind and Engineering, http://www.history.com/shows/america-the-story-of-us/videos/playlists/ (last visited May 22, 2013).
Mankind and Engineering. The History Channel website. 2013. Available at: http://www.history.com/shows/america-the-story-of-us/videos/playlists/. Accessed May 22, 2013.