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Chimpanzee carrying behaviour and the origins of human bipedality

Current Biology, Volume 22, Issue 6, R180-R181

Hockings KJ. , Humle T, Anderson JR. , Biro D, Sousa C, Ohashi G, Matsuzawa T (2007) 
Chimpanzees share forbidden fruit.

PLoS ONE, 2(9): e886