@article{ref1,
title="Prevalence at death. II. Methodological considerations for use in mortality studies",
journal="American journal of public health",
year="1968",
author="Seigel, DG and Markush, R. E.",
volume="58",
number="4",
pages="772-776",
abstract="<p>[Abstract unavailable]</p>",
language="",
issn="0090-0036",
doi="",
url="http://dx.doi.org/"
}