Wrangham, Richard W. (1996). Chimpanzee cultures. Chicago Academy of Sciences, Harvard University Press. hlm. 115–125. ISBN9780674116634. Diakses tanggal 2 July 2011.
Steven Johnson (2003-04-01). "Emotions and the Brain". Discover Magazine. Diakses tanggal 2007-12-10.
doi.org
McBrearty, S. (2005-09-01). "First fossil chimpanzee". Nature. 437 (7055): 105–8. doi:10.1038/nature04008. PMID16136135.Parameter |coauthors= yang tidak diketahui mengabaikan (|author= yang disarankan) (bantuan)
Osvath, Mathias (2009-03-10). "Spontaneous planning for future stone throwing by a male chimpanzee". Curr. Biol. 19 (5): R190–1. doi:10.1016/j.cub.2009.01.010. PMID19278627.
Gardner, R. A., Gardner, B. T. (1969). "Teaching Sign Language to a Chimpanzee". Science. 165 (3894): 664–672. doi:10.1126/science.165.3894.664. PMID5793972.Pemeliharaan CS1: Banyak nama: authors list (link)
McBrearty, S. (2005-09-01). "First fossil chimpanzee". Nature. 437 (7055): 105–8. doi:10.1038/nature04008. PMID16136135.Parameter |coauthors= yang tidak diketahui mengabaikan (|author= yang disarankan) (bantuan)
Osvath, Mathias (2009-03-10). "Spontaneous planning for future stone throwing by a male chimpanzee". Curr. Biol. 19 (5): R190–1. doi:10.1016/j.cub.2009.01.010. PMID19278627.
Gardner, R. A., Gardner, B. T. (1969). "Teaching Sign Language to a Chimpanzee". Science. 165 (3894): 664–672. doi:10.1126/science.165.3894.664. PMID5793972.Pemeliharaan CS1: Banyak nama: authors list (link)