Lepre (2010). "New magnetostratigraphy for the Olduvai Subchron in the Koobi Fora Formation, northwest Kenya, with implications for early Homo". Earth and Planetary Science Letters. 290 (3–4): 362. doi:10.1016/j.epsl.2009.12.032..
"paleo-magnetic results of this study delimit the age of KNM-ER 3733 to 1.78–1.48 Ma, making it one of the most securely dated fossils ofearly African H. erectus when compared to the oldest Homo fossils from Europe and Asia."
