@article{ref1,
title="Maternal mortality",
journal="Nederlandsch Tijdschrift Voor Verloskunde en Gynaecologie",
year="1968",
author="Willemsen, H.",
volume="68",
number="3",
pages="228-235",
abstract="<p>[Abstract unavailable]</p><p>Language: nl</p>",
language="nl",
issn="0301-2247",
doi="",
url="http://dx.doi.org/"
}