@article{ref1,
title="On the need for the rare disease assumption in some case-control studies",
journal="Injury prevention",
year="2001",
author="Cummings, P. and Koepsell, Thomas D.",
volume="7",
number="3",
pages="254-254",
abstract="Abstract unavailable.",
language="en",
issn="1353-8047",
doi="",
url="http://dx.doi.org/"
}