@article{ref1,
title="Study on the duration of working disability in shipbuilding workers with backache",
journal="Beitrage zur Orthopadie und Traumatologie",
year="1972",
author="Nauwald, G.",
volume="19",
number="5",
pages="289-292",
abstract="<p>[Abstract unavailable]</p><p>Language: de</p>",
language="de",
issn="0005-8149",
doi="",
url="http://dx.doi.org/"
}