@article{ref1,
title="The origin of war: New 14C dates from ancient Mexico",
journal="Proceedings of the National Academy of Sciences of the United States of America",
year="2003",
author="Flannery, K. V. and Marcus, J.",
volume="100",
number="20",
pages="11801-11805",
abstract="<p>[Abstract unavailable]</p>",
language="",
issn="0027-8424",
doi="10.1073/pnas.1934526100",
url="http://dx.doi.org/10.1073/pnas.1934526100"
}