@article{ref1,
title="Calculation of a safety factor in setting health based permissible levels for occupational exposure. II. Comparison of extrapolated and published permissible levels",
journal="International archives of occupational and environmental health",
year="1979",
author="Zielhuis, R. L. and van der Kreek, F. W.",
volume="42",
number="3-4",
pages="203-215",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0340-0131",
doi="",
url="http://dx.doi.org/"
}