James D. Hart and and Phillip W. Leininger. "Clarke, John." The Oxford Companion to American Literature. Oxford University Press. 1995. Encyclopedia.com. 22 Nov. 2009 <http://www.encyclopedia.com>.
James D. Hart and and Phillip W. Leininger. "Clarke, John." The Oxford Companion to American Literature. Oxford University Press. 1995. Encyclopedia.com. (November 22, 2009). http://www.encyclopedia.com/doc/1O123-ClarkeJohn.html
James D. Hart and and Phillip W. Leininger. "Clarke, John." The Oxford Companion to American Literature. Oxford University Press. 1995. Retrieved November 22, 2009 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O123-ClarkeJohn.html