@article{ref1,
title="A study of the use of mouth protection in the sport of ice hockey",
journal="Penn dental journal",
year="1975",
author="Cohen, S.",
volume="77",
number="2-3",
pages="33-34",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0031-4331",
doi="",
url="http://dx.doi.org/"
}