@article{ref1,
title="Injury rates in high school football. A comparison of synthetic surfaces and grass fields",
journal="Clinical orthopaedics and related research",
year="1974",
author="Adkison, J. W. and Requa, R. K. and Garrick, J. G.",
volume="",
number="99",
pages="131-136",
abstract="<p>[Abstract unavailable]  Keywords: American football </p> <p>Language: en</p>",
language="en",
issn="0009-921X",
doi="",
url="http://dx.doi.org/"
}