@article{ref1,
title="Contact sports in junior high school",
journal="Texas medicine",
year="1967",
author="Collins, H. R.",
volume="63",
number="10",
pages="67-69",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0040-4470",
doi="",
url="http://dx.doi.org/"
}