@article{ref1,
title="Urban growth and population densities",
journal="Demography",
year="1973",
author="Guest, A. M.",
volume="10",
number="1",
pages="53-69",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0070-3370",
doi="",
url="http://dx.doi.org/"
}