@article{Keller2001,
author = {Keller, M.C. and Nesse, R.M. and Hofferth, S. },
title= {The Trivers–Willard hypothesis of parental investment: No effect in the contemporary United States},
year = {2001},
doi = {10.1016/S1090-5138(01)00075-7},
journal = {Evolution and Human Behavior},
volume = {22},
pages = {343--360},
}