@article{ref1,
title="On basketballs and heartbeats",
journal="Epidemiology",
year="1991",
author="Powell, Kenneth E.",
volume="2",
number="1",
pages="3-5",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="1044-3983",
doi="",
url="http://dx.doi.org/"
}