@inbook{Euler2011,
author = {Euler, H.A. },
title= {Grandparents and extended kin},
year = {2011},
editor = {Salmon, C.A.},
editor = {Shackelford, T.K.},
booktitle = {The oxford handbook on evolutionary family psychology},
address = {Oxford},
publisher = {University Press},
pages = {181--210},
}