@article{ref1,
title="The effects of sleep deprivation upon motor performance of ninth-grade students",
journal="Journal of sports medicine and physical fitness",
year="1972",
author="Copes, K. and Rosentswieg, J.",
volume="12",
number="1",
pages="47-53",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0022-4707",
doi="",
url="http://dx.doi.org/"
}