@article{Kramer2002,
author = {Kramer, K.L. and Boone, J.L. },
title= {Why intensive agriculturalists have higher fertility: A household energy budget approach},
year = {2002},
doi = {10.1086/340239},
journal = {Current Anthropology},
volume = {43},
number = {3},
pages = {511--517},
}