Black leader, educator and diplomat John Mercer Langston is believed to have been the first black person ever elected to public office in the United States.
John Mercer Langston. (2013). The Biography Channel website. Retrieved 01:03, May 20, 2013, from http://www.biography.com/people/john-mercer-langston-9373265.
John Mercer Langston. [Internet]. 2013. The Biography Channel website. Available from: http://www.biography.com/people/john-mercer-langston-9373265 [Accessed 20 May 2013].
"John Mercer Langston." 2013. The Biography Channel website. May 20 2013, 01:03 http://www.biography.com/people/john-mercer-langston-9373265.
"John Mercer Langston," The Biography Channel website, 2013, http://www.biography.com/people/john-mercer-langston-9373265 [accessed May 20, 2013].
"John Mercer Langston," The Biography Channel website, http://www.biography.com/people/john-mercer-langston-9373265 (accessed May 20, 2013).
John Mercer Langston [Internet]. The Biography Channel website; 2013 [cited 2013 May 20] Available from: http://www.biography.com/people/john-mercer-langston-9373265.
John Mercer Langston, http://www.biography.com/people/john-mercer-langston-9373265 (last visited May 20, 2013).
John Mercer Langston. The Biography Channel website. 2013. Available at: http://www.biography.com/people/john-mercer-langston-9373265. Accessed May 20, 2013.