Lewis and Clark return. (2013). The History Channel website. Retrieved 7:31, May 22, 2013, from http://www.history.com/this-day-in-history/lewis-and-clark-return.
Lewis and Clark return. [Internet]. 2013. The History Channel website. Available from: http://www.history.com/this-day-in-history/lewis-and-clark-return [Accessed 22 May 2013].
“Lewis and Clark return.” 2013. The History Channel website. May 22 2013, 7:31 http://www.history.com/this-day-in-history/lewis-and-clark-return.
“Lewis and Clark return,” The History Channel website, 2013, http://www.history.com/this-day-in-history/lewis-and-clark-return [accessed May 22, 2013].
“Lewis and Clark return,” The History Channel website, http://www.history.com/this-day-in-history/lewis-and-clark-return (accessed May 22, 2013).
Lewis and Clark return [Internet]. The History Channel website; 2013 [cited 2013 May 22] Available from: http://www.history.com/this-day-in-history/lewis-and-clark-return.
Lewis and Clark return, http://www.history.com/this-day-in-history/lewis-and-clark-return (last visited May 22, 2013).
Lewis and Clark return. The History Channel website. 2013. Available at: http://www.history.com/this-day-in-history/lewis-and-clark-return. Accessed May 22, 2013.