The Sixth Rhino: A Taxonomic Re-Assessment of the Critically Endangered Northern White Rhinoceros Groves, Colin P. ; Fernando, Prithiviraj ; Robovský, Jan Abstract Publication: PLoS ONE Pub Date: April 2010 DOI: 10.1371/journal.pone.0009703 Bibcode: 2010PLoSO...5.9703G