@article{ref1,
title="Exact road geometry output program for retroreflective road sign performance",
journal="Transportation research record",
year="1993",
author="Uding, Kenneth D.",
volume="1421",
number="",
pages="61-61",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0361-1981",
doi="",
url="http://dx.doi.org/"
}