@article{ref1,
title="Epidemiology on the elementary school playground",
journal="Journal of school health",
year="1986",
author="Dolphin, N. W.",
volume="56",
number="3",
pages="111-112",
abstract="<p>[Abstract unavailable]</p> <p>Language: en</p>",
language="en",
issn="0022-4391",
doi="",
url="http://dx.doi.org/"
}