@article{ref1,
title="Performance rhythm of adolescents",
journal="Zeitschrift fur Arztliche Fortbildung (Jena)",
year="1957",
author="Prokop, L.",
volume="51",
number="21-22",
pages="998-1000",
abstract="<p>[Abstract unavailable]</p><p>Language: de</p>",
language="de",
issn="0044-2178",
doi="",
url="http://dx.doi.org/"
}