@article{ref1,
title="Cumulative effects of sleep restriction on daytime sleepiness",
journal="Psychophysiology",
year="1981",
author="Carskadon, Mary A. and Dement, W. C.",
volume="18",
number="2",
pages="107-113",
abstract="<p>[Abstract unavailable]</p> <p>Language: en</p>",
language="en",
issn="0048-5772",
doi="",
url="http://dx.doi.org/"
}