Causal factors underlying the dramatic decline of the Sumatran orang-utan
20 December 2001 Science News
Robertson J. M. Y. & van Schaik C. P. (2001). Causal factors underlying the dramatic decline of the Sumatran orang-utan. Oryx 35(1): 26-38
http://journals.cambridge.org/action/displayJournal?jid=ORX
