@article{ref1,
title="Extremal principles for simulating traffic flow in a network",
journal="Proceedings of the National Academy of Sciences of the United States of America",
year="1958",
author="Charnes, A. and Cooper, W. W.",
volume="44",
number="2",
pages="201-204",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0027-8424",
doi="",
url="http://dx.doi.org/"
}