@article{ref1,
title="Preventive aspects of helmet safety",
journal="Western journal of medicine",
year="1993",
author="Hadden, T. A. and Benzel, E. C.",
volume="158",
number="1",
pages="69-70",
abstract="Abstract unavailable.",
language="",
issn="0093-0415",
doi="",
url="http://dx.doi.org/"
}