@article{ref1,
title="Thoughts about roles and relations: An old document revisited",
journal="Social networks",
year="1988",
author="Winship, Christopher",
volume="10",
number="3",
pages="209-231",
abstract="<p>[Abstract unavailable]</p>",
language="",
issn="0378-8733",
doi="10.1016/0378-8733(88)90013-5",
url="http://dx.doi.org/10.1016/0378-8733(88)90013-5"
}