@article{ref1,
title="Studies in Political Areas. II. Intellectual, Political, and Economic Effects of Large Areas",
journal="American journal of sociology",
year="1898",
author="Ratzel, Friedrich",
volume="3",
number="4",
pages="449-463",
abstract="<p>[Abstract unavailable]</p>",
language="",
issn="0002-9602",
doi="10.1086/210723",
url="http://dx.doi.org/10.1086/210723"
}