Construction begins on the Sutro Tunnel in Virginia City, Nevada. (2013). The History Channel website. Retrieved 9:35, May 22, 2013, from http://www.history.com/this-day-in-history/construction-begins-on-the-sutro-tunnel-in-virginia-city-nevada.
Construction begins on the Sutro Tunnel in Virginia City, Nevada. [Internet]. 2013. The History Channel website. Available from: http://www.history.com/this-day-in-history/construction-begins-on-the-sutro-tunnel-in-virginia-city-nevada [Accessed 22 May 2013].
“Construction begins on the Sutro Tunnel in Virginia City, Nevada.” 2013. The History Channel website. May 22 2013, 9:35 http://www.history.com/this-day-in-history/construction-begins-on-the-sutro-tunnel-in-virginia-city-nevada.
“Construction begins on the Sutro Tunnel in Virginia City, Nevada,” The History Channel website, 2013, http://www.history.com/this-day-in-history/construction-begins-on-the-sutro-tunnel-in-virginia-city-nevada [accessed May 22, 2013].
“Construction begins on the Sutro Tunnel in Virginia City, Nevada,” The History Channel website, http://www.history.com/this-day-in-history/construction-begins-on-the-sutro-tunnel-in-virginia-city-nevada (accessed May 22, 2013).
Construction begins on the Sutro Tunnel in Virginia City, Nevada [Internet]. The History Channel website; 2013 [cited 2013 May 22] Available from: http://www.history.com/this-day-in-history/construction-begins-on-the-sutro-tunnel-in-virginia-city-nevada.
Construction begins on the Sutro Tunnel in Virginia City, Nevada, http://www.history.com/this-day-in-history/construction-begins-on-the-sutro-tunnel-in-virginia-city-nevada (last visited May 22, 2013).
Construction begins on the Sutro Tunnel in Virginia City, Nevada. The History Channel website. 2013. Available at: http://www.history.com/this-day-in-history/construction-begins-on-the-sutro-tunnel-in-virginia-city-nevada. Accessed May 22, 2013.