"pericardium." A Dictionary of Nursing. Oxford University Press. 2008. Encyclopedia.com. 17 Dec. 2009 <http://www.encyclopedia.com>.
"pericardium." A Dictionary of Nursing. Oxford University Press. 2008. Encyclopedia.com. (December 17, 2009). http://www.encyclopedia.com/doc/1O62-pericardium.html
"pericardium." A Dictionary of Nursing. Oxford University Press. 2008. Retrieved December 17, 2009 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O62-pericardium.html