@article{ref1,
title="The Efficiency of 2 Dimensional Traffic Markers in Referring Commands",
journal="Human factors",
year="1964",
author="Nelson, Thomas M.",
volume="6",
number="4",
pages="359-364",
abstract="[Abstract unavailable]  <p>Language: en<a href=&quot;index.php?fuseaction=journalarticles.editarticle&amp;journalArticleId=81743&quot;></a></p>",
language="en",
issn="0018-7208",
doi="",
url="http://dx.doi.org/"
}