Mine explodes in Oklahoma. (2013). The History Channel website. Retrieved 9:03, May 21, 2013, from http://www.history.com/this-day-in-history/mine-explodes-in-oklahoma.
Mine explodes in Oklahoma. [Internet]. 2013. The History Channel website. Available from: http://www.history.com/this-day-in-history/mine-explodes-in-oklahoma [Accessed 21 May 2013].
“Mine explodes in Oklahoma.” 2013. The History Channel website. May 21 2013, 9:03 http://www.history.com/this-day-in-history/mine-explodes-in-oklahoma.
“Mine explodes in Oklahoma,” The History Channel website, 2013, http://www.history.com/this-day-in-history/mine-explodes-in-oklahoma [accessed May 21, 2013].
“Mine explodes in Oklahoma,” The History Channel website, http://www.history.com/this-day-in-history/mine-explodes-in-oklahoma (accessed May 21, 2013).
Mine explodes in Oklahoma [Internet]. The History Channel website; 2013 [cited 2013 May 21] Available from: http://www.history.com/this-day-in-history/mine-explodes-in-oklahoma.
Mine explodes in Oklahoma, http://www.history.com/this-day-in-history/mine-explodes-in-oklahoma (last visited May 21, 2013).
Mine explodes in Oklahoma. The History Channel website. 2013. Available at: http://www.history.com/this-day-in-history/mine-explodes-in-oklahoma. Accessed May 21, 2013.