Isaac Singer wins Nobel Prize. (2013). The History Channel website. Retrieved 4:24, May 21, 2013, from http://www.history.com/this-day-in-history/isaac-singer-wins-nobel-prize.
Isaac Singer wins Nobel Prize. [Internet]. 2013. The History Channel website. Available from: http://www.history.com/this-day-in-history/isaac-singer-wins-nobel-prize [Accessed 21 May 2013].
“Isaac Singer wins Nobel Prize.” 2013. The History Channel website. May 21 2013, 4:24 http://www.history.com/this-day-in-history/isaac-singer-wins-nobel-prize.
“Isaac Singer wins Nobel Prize,” The History Channel website, 2013, http://www.history.com/this-day-in-history/isaac-singer-wins-nobel-prize [accessed May 21, 2013].
“Isaac Singer wins Nobel Prize,” The History Channel website, http://www.history.com/this-day-in-history/isaac-singer-wins-nobel-prize (accessed May 21, 2013).
Isaac Singer wins Nobel Prize [Internet]. The History Channel website; 2013 [cited 2013 May 21] Available from: http://www.history.com/this-day-in-history/isaac-singer-wins-nobel-prize.
Isaac Singer wins Nobel Prize, http://www.history.com/this-day-in-history/isaac-singer-wins-nobel-prize (last visited May 21, 2013).
Isaac Singer wins Nobel Prize. The History Channel website. 2013. Available at: http://www.history.com/this-day-in-history/isaac-singer-wins-nobel-prize. Accessed May 21, 2013.