@article{ref1,
title="Once more: with safety shafthead equipped",
journal="Zentralblatt fur Arbeitsmedizin und Arbeitsschutz",
year="1971",
author="Lange, U.",
volume="21",
number="7",
pages="225-226",
abstract="<p>[Abstract unavailable]</p><p>Language: de</p>",
language="de",
issn="0044-4049",
doi="",
url="http://dx.doi.org/"
}