@article{Vaupel2009,
author = {Vaupel, J.W.},
title= {Lively Questions for Demographers about Death at Older Ages},
year = {2009},
doi = {10.1111/j.1728-4457.2009.00281.x},
journal = {Population and Development Review},
volume = {35},
number = {2},
pages = {347--356},
}