Wilson, Michael L.; Hauser, Marc D.; Wrangham, Richard W. (2007). "Chimpanzees (Pan troglodytes) Modify Grouping and Vocal Behaviour in Response to Location-Specific Risk". Behaviour. 144 (12): 1621–1653. doi:10.1163/156853907782512137. JSTOR4536536.
Fedurek, Pawel; Machanda, Zarin P.; Schel, Anne M.; Slocombe, Katie E. (2013-07-01). "Pant hoot chorusing and social bonds in male chimpanzees". Animal Behaviour. 86 (1): 189–196. doi:10.1016/j.anbehav.2013.05.010. ISSN0003-3472. S2CID53149158.
Wilson, Michael L.; Hauser, Marc D.; Wrangham, Richard W. (2007). "Chimpanzees (Pan troglodytes) Modify Grouping and Vocal Behaviour in Response to Location-Specific Risk". Behaviour. 144 (12): 1621–1653. doi:10.1163/156853907782512137. JSTOR4536536.
Fedurek, Pawel; Machanda, Zarin P.; Schel, Anne M.; Slocombe, Katie E. (2013-07-01). "Pant hoot chorusing and social bonds in male chimpanzees". Animal Behaviour. 86 (1): 189–196. doi:10.1016/j.anbehav.2013.05.010. ISSN0003-3472. S2CID53149158.
Fedurek, Pawel; Machanda, Zarin P.; Schel, Anne M.; Slocombe, Katie E. (2013-07-01). "Pant hoot chorusing and social bonds in male chimpanzees". Animal Behaviour. 86 (1): 189–196. doi:10.1016/j.anbehav.2013.05.010. ISSN0003-3472. S2CID53149158.