Rocky Marciano retires as world heavyweight champion. (2013). The History Channel website. Retrieved 2:28, May 20, 2013, from http://www.history.com/this-day-in-history/rocky-marciano-retires-as-world-heavyweight-champion.
Rocky Marciano retires as world heavyweight champion. [Internet]. 2013. The History Channel website. Available from: http://www.history.com/this-day-in-history/rocky-marciano-retires-as-world-heavyweight-champion [Accessed 20 May 2013].
“Rocky Marciano retires as world heavyweight champion.” 2013. The History Channel website. May 20 2013, 2:28 http://www.history.com/this-day-in-history/rocky-marciano-retires-as-world-heavyweight-champion.
“Rocky Marciano retires as world heavyweight champion,” The History Channel website, 2013, http://www.history.com/this-day-in-history/rocky-marciano-retires-as-world-heavyweight-champion [accessed May 20, 2013].
“Rocky Marciano retires as world heavyweight champion,” The History Channel website, http://www.history.com/this-day-in-history/rocky-marciano-retires-as-world-heavyweight-champion (accessed May 20, 2013).
Rocky Marciano retires as world heavyweight champion [Internet]. The History Channel website; 2013 [cited 2013 May 20] Available from: http://www.history.com/this-day-in-history/rocky-marciano-retires-as-world-heavyweight-champion.
Rocky Marciano retires as world heavyweight champion, http://www.history.com/this-day-in-history/rocky-marciano-retires-as-world-heavyweight-champion (last visited May 20, 2013).
Rocky Marciano retires as world heavyweight champion. The History Channel website. 2013. Available at: http://www.history.com/this-day-in-history/rocky-marciano-retires-as-world-heavyweight-champion. Accessed May 20, 2013.