Campus Verlag, Frankfurt am Main 2008, ISBN 978-3-593-38515-0External linksThe author's website.Awon ara Austria.. 
Iṣẹtẹ̀lé gbogbo Outme ti mu Yewa pe "leyin ọdun 6.5 [million]  idagbajade otooto, awọn iyatọ larin Chimpanz ati eniyan tóbijù awọn to wa larin awọn eniyan ti wọn ko ni ibatan mo ra wọn lo lemẹwa ati won dínjú lemewa larin awọn eku ati ọ̀mọ̀lé/èkúté/ 