@article{ref1,
title="Structural covariates of homicide rates: are there any invariances across time and social space",
journal="American journal of sociology",
year="1990",
author="Land, K. C. and McCall, Patricia L. and Cohen, L. E.",
volume="95",
number="4",
pages="922-963",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0002-9602",
doi="10.1086/229381",
url="http://dx.doi.org/10.1086/229381"
}