The following bibliography has been generated by bringing together all references provided by our content partners. There may be duplication.

References

• 1. IUCN Red List (September, 2007) http://www.iucnredlist.org
• 2. Macdonald, D. (2001) The New Encyclopedia of Mammals. Oxford University Press, Oxford.
• 2009. Among apes, teeth are made for the toughest times. EurekAlert! [Internet],
• 3. CITES (July, 2002) http://www.cites.org
• 4. Gunung Palung Orang-utan Project (July, 2002) http://www.fas.harvard.edu/~gporang/
• 5. Animal Diversity Web (July, 2002) http://animaldiversity.ummz.umich.edu/accounts/pongo/p._pygmaeus$narrative.html
• 6. Burnie, D. (2001) Animal. Dorling Kindersley, London.
• 7. Lorenz, M. (2004) Pers. Comm.
• 8. WWF Threatened Species Accounts (July, 2002) http://www.panda.org/about_wwf/what_we_do/species/what_we_do/flagship_species/great_apes/orangutan/index.cfm
• 9. Van Schaik, C.P., Monk, K.A. and Yarrow Robertson, J.M. (2001) Dramatic decline in orang-utan numbers in the Leuser Ecosystem, Northern Sumatra. Oryx, 35 (1): 14 - 25.
• Constantino PJ; Lucas PW; Lee JJ; Lawn BR. 2009. The influence of fallback foods on great ape tooth enamel. Am J Phys Anthropol. 140(4): 653-60.
• Groves, C.P. 1971. Pongo pygmaeus. Mammalian Species, No. 4, pp. 1-6. Published by the American Society of Mammalogists.
• Nowak, R.M., and J.L. Paradiso. 1983. Walker's Mammals of the World, 4th ed. Johns Hopkins University Press, Baltimore.
• Richard Weigl (2005) Longevity of Mammals in Captivity; from the Living Collections of the World. Kleine Senckenberg-Reihe 48: Stuttgart.
• Wich et al. (2004) Life history of wild Sumatran orangutans (Pongo abelii). J Hum Evol, 47:385-398.
• Wilson, Don E., and DeeAnn M. Reeder, eds. 1993. Mammal Species of the World: A Taxonomic and Geographic Reference, 2nd ed., 3rd printing. xviii + 1207
• Wilson, Don E., and F. Russell Cole. 2000. Common Names of Mammals of the World. xiv + 204