@article{ref1,
title="The Rivalry of Social Groups",
journal="American journal of sociology",
year="1911",
author="Vincent, George E.",
volume="16",
number="4",
pages="469-484",
abstract="<p>[Abstract unavailable]</p>",
language="",
issn="0002-9602",
doi="10.1086/211909",
url="http://dx.doi.org/10.1086/211909"
}