@inbook{Mace2005,
author = {Mace, R. and Sear, R.},
title= {Are humans cooperative breeders? },
year = {2005},
editor = {Voland, E.},
editor = {Chasiotis, A.},
editor = {Schiefenhoevel, W. },
booktitle = {Grandmotherhood: The evolutionary significance of the second half of female life},
address = {Piscataway},
publisher = {Rutgers University Press},
pages = {143--159},
}