@article{ref1,
title="Field studies of shiftwork: ii. temporal patterns in psychophysiological activation in workers alternating between night and day work",
journal="Ergonomics",
year="1977",
author="Akerstedt, Torbjörn and Patkal, P. and Dahlgren, K.",
volume="20",
number="6",
pages="621-631",
abstract="<p>[Abstract unavailable]</p> <p>Language: en</p>",
language="en",
issn="0014-0139",
doi="",
url="http://dx.doi.org/"
}