@article{Coall2010,
author = {Coall, David A. and Hertwig, Ralph},
title= {Grandparental investment: Past, present, and future},
year = {2010},
URL = {10.1017/S0140525X09991105},
journal = {Behavioral and Brain Sciences},
volume = {33},
number = {01},
pages = {1--19},
}