"Normal." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 24 Dec. 2009 <http://www.encyclopedia.com>.
"Normal." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (December 24, 2009). http://www.encyclopedia.com/doc/1O999-normal.html
"Normal." The Oxford Pocket Dictionary of Current English. 2009. Retrieved December 24, 2009 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-normal.html