@article{ref1,
title="Circadian variations in human performance and work efficiency",
journal="Acta physiologica polonica",
year="1979",
author="Wojtczak-Jaroszowa, J.",
volume="30",
number="Suppl 19",
pages="201-207",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0044-6033",
doi="",
url="http://dx.doi.org/"
}