KERMIT L. HALL. "Four Horsemen." The Oxford Companion to the Supreme Court of the United States. Oxford University Press. 2005. Encyclopedia.com. 2 Dec. 2009 <http://www.encyclopedia.com>.
KERMIT L. HALL. "Four Horsemen." The Oxford Companion to the Supreme Court of the United States. Oxford University Press. 2005. Encyclopedia.com. (December 2, 2009). http://www.encyclopedia.com/doc/1O184-FourHorsemen.html
KERMIT L. HALL. "Four Horsemen." The Oxford Companion to the Supreme Court of the United States. Oxford University Press. 2005. Retrieved December 02, 2009 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O184-FourHorsemen.html