AILSA ALLABY and MICHAEL ALLABY. "Australopithecus." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. 7 Dec. 2009 <http://www.encyclopedia.com>.
AILSA ALLABY and MICHAEL ALLABY. "Australopithecus." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. (December 7, 2009). http://www.encyclopedia.com/doc/1O13-Australopithecus.html
AILSA ALLABY and MICHAEL ALLABY. "Australopithecus." A Dictionary of Earth Sciences. 1999. Retrieved December 07, 2009 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O13-Australopithecus.html