@article{ref1,
title="Concussion in teenage athletes",
journal="Adolescent medicine: state of the art reviews",
year="2015",
author="Walter, Kevin D. and Halstead, Mark E.",
volume="26",
number="1",
pages="39-52",
abstract="<p>[Abstract unavailable]</p> <p>Language: en</p>",
language="en",
issn="1934-4287",
doi="",
url="http://dx.doi.org/"
}