@article{ref1,
title="Study of school playgrounds and aggressive behavior of children",
journal="Aggressive behavior",
year="2001",
author="Angulo, JC and Ortega, R. and Neto, C.",
volume="27",
number="3",
pages="167-167",
abstract="<p>[Abstract unavailable]</p>",
language="en",
issn="0096-140X",
doi="",
url="http://dx.doi.org/"
}