@article{ref1,
title="Industrial hygiene -- retrospect and prospect",
journal="American journal of public health",
year="1939",
author="Bloomfield, JJ",
volume="29",
number="11",
pages="1215-1224",
abstract="<p>[Abstract unavailable]</p>",
language="",
issn="0090-0036",
doi="",
url="http://dx.doi.org/"
}