@article{ref1,
title="A Portable Photometer for the Testing of Reflective Road Signs",
journal="Journal of scientific instruments",
year="1954",
author="Giovanelli, RG",
volume="31",
number="4",
pages="126-128",
abstract="[Abstract unavailable]  <p>Language: en</p>",
language="en",
issn="0950-7671",
doi="",
url="http://dx.doi.org/"
}