@inbook{Hawkes1989,
author = {Hawkes, K. and O’Connell, J.F. and Blurton Jones, N.G.},
title= {Hardworking Hadza grandmothers},
year = {1989},
editor = {Standen, V.},
editor = {Foley, R.A. },
booktitle = {Comparative socioecology: The behavioural ecology of humans and other mammals},
address = {Oxford},
publisher = {Blackwell},
}