@article{ref1,
title="Comments on the night duty and shift system",
journal="Sangyo Igaku",
year="1978",
author="",
volume="20",
number="5",
pages="308-329",
abstract="<p>[Abstract unavailable]</p><p>Language: ja</p>",
language="ja",
issn="0047-1879",
doi="",
url="http://dx.doi.org/"
}