JOHN CANNON. "Merton, Walter de." The Oxford Companion to British History. Oxford University Press. 2002. Encyclopedia.com. 22 Nov. 2009 <http://www.encyclopedia.com>.
JOHN CANNON. "Merton, Walter de." The Oxford Companion to British History. Oxford University Press. 2002. Encyclopedia.com. (November 22, 2009). http://www.encyclopedia.com/doc/1O110-MertonWalterde.html
JOHN CANNON. "Merton, Walter de." The Oxford Companion to British History. Oxford University Press. 2002. Retrieved November 22, 2009 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O110-MertonWalterde.html