@article{ref1,
title="Prevention of preterm birth",
journal="New England journal of medicine",
year="1998",
author="Devitt, N.",
volume="339",
number="25",
pages="1859-1860",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0028-4793",
doi="",
url="http://dx.doi.org/"
}