Osvath, Mathias (2009-03-10). "Spontaneous planning for future stone throwing by a male chimpanzee". Current Biology. Elsevier. 19 (5): R190–R191. doi:10.1016/j.cub.2009.01.010. PMID19278627.
Osvath, Mathias (2009-03-10). "Spontaneous planning for future stone throwing by a male chimpanzee". Current Biology. Elsevier. 19 (5): R190–R191. doi:10.1016/j.cub.2009.01.010. PMID19278627.