@article{ref1,
title="Annual cycle of the frequency of demand for safety equipment by engine-drivers of the Deutsche Bundesbahn (German Federal Railway)",
journal="Internationales Archiv für Arbeitsmedizin",
year="1973",
author="Hildebrandt, G. and Rohmert, W. and Rutenfranz, J.",
volume="31",
number="2",
pages="73-80",
abstract="<p>[Abstract unavailable]</p> <p>Language: de</p>",
language="de",
issn="0020-5923",
doi="",
url="http://dx.doi.org/"
}