Semaw, Sileshi (בדצמבר 2000). "The World's Oldest Stone Artefacts from Gona, Ethiopia: Their Implications for Understanding Stone Technology and Patterns of Human Evolution Between 2·6–1·5 Million Years Ago". Journal of Archaeological Science. 27 (12): 1197–1214. doi:10.1006/jasc.1999.0592. {{cite journal}}: (עזרה)
nih.gov
ncbi.nlm.nih.gov
Asfaw B, White T, Lovejoy O, Latimer B, Simpson S, Suwa G. (1999). "Australopithecus garhi: a new species of early hominid from Ethiopia". Science. 284(5414):629-35. PMID10213683
de Heinzelin J, Clark JD, White T, Hart W, Renne P, WoldeGabriel G, Beyene Y, Vrba E. (1999). Environment and behavior of 2.5-million-year-old Bouri hominids. Science. 284(5414):625-9. PMID10213682
