@article{ref1,
title="Lead and hyperactivity",
journal="Lancet",
year="1972",
author="David, O. and Clark, J. and Voeller, K.",
volume="2",
number="7783",
pages="900-903",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0140-6736",
doi="",
url="http://dx.doi.org/"
}