@article{Bongaarts2003,
author = {Bongaarts, J. and Feeney, G.},
title= {Estimating mean lifetime},
year = {2003},
doi = {10.1073/pnas.2035060100},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
volume = {100},
number = {23},
pages = {13127--13133},
}