@article{ref1,
title="Inversion of the sleep wakefulness pattern: effects on circadian variations in psychophysiological activation",
journal="Ergonomics",
year="1977",
author="Akerstedt, Torbjörn",
volume="20",
number="5",
pages="459-474",
abstract="<p>[Abstract unavailable]</p> <p>Language: en</p>",
language="en",
issn="0014-0139",
doi="",
url="http://dx.doi.org/"
}