@article{Kramer2002,
author = {Kramer, K.L.},
title= {Helping behavior among Maya children},
year = {2002},
doi = {10.1007/s12110-002-1011-8},
URL = {https://doi.org/10.1007/s12110-002-1011-8},
volume = {13},
number = {2},
pages = {299--325},
}