@article{ref1,
title="Visual performance and traffic safety",
journal="Hefte zur Unfallheilkunde",
year="1975",
author="Piper, H. E.",
volume="",
number="121",
pages="392-400",
abstract="Abstract unavailable.",
language="",
issn="0085-1469",
doi="",
url="http://dx.doi.org/"
}