@article{ref1,
title="Dangerous metal chips",
journal="Zentralblatt fur Arbeitsmedizin und Arbeitsschutz",
year="1969",
author="Knop, W.",
volume="19",
number="6",
pages="161-162",
abstract="<p>[Abstract unavailable]</p><p>Language: de</p>",
language="de",
issn="0044-4049",
doi="",
url="http://dx.doi.org/"
}