Stratigraphy of Beds I Through IV, Olduvai Gorge, Tanganyika R. M. Walker, P. B. Price, R. L. Fleischer, R. L. Hay, L.S.B. Leakey • 1965
The Potassium-Argon Dating of Late Cenozoic Rocks in East Africa and Italy [and Comments and Reply] H. E. Wright, , J. R. Richards et al. • 1965