@article{ref1,
title="An Analysis of Traffic Flow",
journal="Operations research",
year="1959",
author="Greenberg, H",
volume="7",
number="1",
pages="79-85",
abstract="[Abstract unavailable]  <p>Language: en</p>",
language="en",
issn="0030-364X",
doi="",
url="http://dx.doi.org/"
}