@article{ref1,
title="Polyolefin foam protective sports mouthguard",
journal="Journal of clinical orthodontics: JCO",
year="1999",
author="Croll, T. P.",
volume="33",
number="3",
pages="168-170",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0022-3875",
doi="",
url="http://dx.doi.org/"
}