@article{ref1,
title="The usefulness of formulae in traffic engineering and road safety",
journal="Accident analysis and prevention",
year="1972",
author="Smeed, R. J.",
volume="4",
number="4",
pages="303-312",
abstract="<p>[Abstract unavailable]</p>",
language="en",
issn="0001-4575",
doi="",
url="http://dx.doi.org/"
}