@article{ref1,
title="Changing concepts in occupational health",
journal="American journal of public health",
year="1969",
author="Schilling, R. S.",
volume="59",
number="8",
pages="1366-1375",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0090-0036",
doi="",
url="http://dx.doi.org/"
}